24 June 2010
I refined the Macros program so as to present users with the option to choose whether die is centered or at the edge of the flag. Besides that, I also performed ball shear, die shear and wire pull
25 June 2010
I spent my last day here at NXP Semiconductors reminiscing and tying up loose ends, as well as bidding farewell to friends here
Saturday, June 26, 2010
Wednesday, June 23, 2010
16 - 23 June 2010
16 June 2010
Went for check-up
17 June 2010
I updated quite a large amount of PMD. I was also assigned to take top-view, side-view and wedge bond images on decapped products.
18 June 2010
I refined the Macros program that I had previously created. It will now provide suggestions for suitable major flag vertical length given die size remains unchanged and if present major flag vertical length results in cracked die occurrences.
21 June 2010
Again, I refined the Macros program by altering the position images will be prompted out so that it would be better placed for user to take a comprehensive look. I also changed the all the links for prompting pictures so that those pictures can be displayed without user having to painstakingly change the link manually in Visual Basic Editor every time that folder is to be used in another computer. Logically, this makes my Macros program more user friendly. Furthermore, I had also added a Read_Me notepad file to address possible failure to execute Macros in newer version (2007) of Excel as well as providing an explicit explanation of the assumptions employed in generating the Macros.
22 June 2010
Updated huge number of PMDs. Insipidity and monotony are quickly coming into play.
23 June 2010
I was still facing a deluge of PMDs to be updated and was finally able to finish all 78 PMDs by today. At the end of the day, I was ineluctably dizzy and flummoxed. Some of the information that I had updated are 12NC number, family type, package name, test job name, product family name, marking code, status, crystal identification numbers, wafer quantity, number of dies, number of wires, back metal, wire type, subpackage type, subpackage description, diffusion and so much more.
Went for check-up
17 June 2010
I updated quite a large amount of PMD. I was also assigned to take top-view, side-view and wedge bond images on decapped products.
18 June 2010
I refined the Macros program that I had previously created. It will now provide suggestions for suitable major flag vertical length given die size remains unchanged and if present major flag vertical length results in cracked die occurrences.
21 June 2010
Again, I refined the Macros program by altering the position images will be prompted out so that it would be better placed for user to take a comprehensive look. I also changed the all the links for prompting pictures so that those pictures can be displayed without user having to painstakingly change the link manually in Visual Basic Editor every time that folder is to be used in another computer. Logically, this makes my Macros program more user friendly. Furthermore, I had also added a Read_Me notepad file to address possible failure to execute Macros in newer version (2007) of Excel as well as providing an explicit explanation of the assumptions employed in generating the Macros.
22 June 2010
Updated huge number of PMDs. Insipidity and monotony are quickly coming into play.
23 June 2010
I was still facing a deluge of PMDs to be updated and was finally able to finish all 78 PMDs by today. At the end of the day, I was ineluctably dizzy and flummoxed. Some of the information that I had updated are 12NC number, family type, package name, test job name, product family name, marking code, status, crystal identification numbers, wafer quantity, number of dies, number of wires, back metal, wire type, subpackage type, subpackage description, diffusion and so much more.
Friday, June 18, 2010
14 - 16 June 2010
14 June 2010
I continued working on the report of determining optimum process parameter for PHICOM3 24k wire bonder using 50um gold wire. In the mean time, I gained cognizance on the input parameters considered significant in die bonding as well as wire bonding processes. First off, factors influencing die bonding are temperature, bond force and process delay. On the other hand, spark current, spark time, bond force and USG influence wire bonding process. USG stands for ultrasonic generator. At the other end of the spectrum, output responses akin to die bonding process are die shear analysis and Dvth analysis. For die shear analysis, die sheared pictures will be taken to analyze the Si/Au remains, which must be greater than 75% to be considered acceptable. As for Dvth analysis, cross sectional pictures on die bonded lead frame will be taken to be perceived for any gaps between die and lead frame as well as the presence of copper interconnect. On the other hand, for wire bonding process, ball diameter, ball height, ball shear and wire pull are the output responses.
USG plays a role in allowing the ball bond to be attached nicely to the bondpad. USG, together with bond force, are preponderant in influencing ball bond strength; while spark current and spark time are predominantly influential in ball size. I was taught that low spark current and spark time, together with high bond force and USG are not acceptable. This particular combination of input parameters will engender with ball that may not have any height at all.
I also learnt that the range of ball diameter is governed by the bondpad size. It should be within the bondpad size to avoid offbond. Besides that, the ball height lower limit should be half of the wire diameter, while its upper limit must be one and a half that of the wire diameter.
Moving on to Minitab, I had gained knowledge on generating various plots, which are momentous in analyzing sets of data. First off, normal and Pareto plots will enable us to determine the significance of input parameters. Next, optimization plot will help us in determining the optimum process parameters. Furthermore, contour plot is used when we intend to determine the range of feasible process parameters.
15 June 2010
Previously, I learnt that temperature, bond force and process delay are significant parameters influencing die-bonding process. However, die-bonding process can be categorized into eutectic bonding and epoxy bonding. Those 3 factors are only significant to eutectic bonding. As for epoxy bonding, only bond force is significant. Even so, its influence in the epoxy bonding is still small.
16 June 2010
Went to hospital for follow-up on my injured spine.
I continued working on the report of determining optimum process parameter for PHICOM3 24k wire bonder using 50um gold wire. In the mean time, I gained cognizance on the input parameters considered significant in die bonding as well as wire bonding processes. First off, factors influencing die bonding are temperature, bond force and process delay. On the other hand, spark current, spark time, bond force and USG influence wire bonding process. USG stands for ultrasonic generator. At the other end of the spectrum, output responses akin to die bonding process are die shear analysis and Dvth analysis. For die shear analysis, die sheared pictures will be taken to analyze the Si/Au remains, which must be greater than 75% to be considered acceptable. As for Dvth analysis, cross sectional pictures on die bonded lead frame will be taken to be perceived for any gaps between die and lead frame as well as the presence of copper interconnect. On the other hand, for wire bonding process, ball diameter, ball height, ball shear and wire pull are the output responses.
USG plays a role in allowing the ball bond to be attached nicely to the bondpad. USG, together with bond force, are preponderant in influencing ball bond strength; while spark current and spark time are predominantly influential in ball size. I was taught that low spark current and spark time, together with high bond force and USG are not acceptable. This particular combination of input parameters will engender with ball that may not have any height at all.
I also learnt that the range of ball diameter is governed by the bondpad size. It should be within the bondpad size to avoid offbond. Besides that, the ball height lower limit should be half of the wire diameter, while its upper limit must be one and a half that of the wire diameter.
Moving on to Minitab, I had gained knowledge on generating various plots, which are momentous in analyzing sets of data. First off, normal and Pareto plots will enable us to determine the significance of input parameters. Next, optimization plot will help us in determining the optimum process parameters. Furthermore, contour plot is used when we intend to determine the range of feasible process parameters.
15 June 2010
Previously, I learnt that temperature, bond force and process delay are significant parameters influencing die-bonding process. However, die-bonding process can be categorized into eutectic bonding and epoxy bonding. Those 3 factors are only significant to eutectic bonding. As for epoxy bonding, only bond force is significant. Even so, its influence in the epoxy bonding is still small.
16 June 2010
Went to hospital for follow-up on my injured spine.
Saturday, June 12, 2010
8-11 June 2010
8 June 2010
Again, I refined the Macro program akin to my project. I added a “Clear All” button. As its name implies, this button will present user with the choice of deleting all contents in that active Excel sheet. Besides that, I also altered the appearance of “Start/Restart” button and “Helpful Illustration” button. Then, I presented my work to my supervisors, Mr. Melvin, Miss Manggala and Miss June. Subsequently, I helped Miss Manggala in completing her engineering report on Business Line General Application (BLGA) products.
9 June 2010
I continued helping Miss Manggala on her report.
10 June 2010
I completed another engineering report Miss Manggala wanted me to help her with, which is to determine the optimum parameter setting for ADAT3 die bonding process for Bim16A on SOT363 products. For this feasibility report, I used Minitab to perform many simulations to determine the optimum set of parameters. Furthermore, I continued post project days by updating Product Master Data (PMD) as well as corresponding bonding diagrams on the intranet.
11 June 2010
Today, I updated some bonding diagrams. These bonding diagrams that I had updated are meant for new products which are just introduced. Besides that, I also helped Miss Manggala on another engineering report, which is aimed to determine the optimum process parameters for PHICOM3 24k wire bonding machine using 50um diameter gold wire.
Again, I refined the Macro program akin to my project. I added a “Clear All” button. As its name implies, this button will present user with the choice of deleting all contents in that active Excel sheet. Besides that, I also altered the appearance of “Start/Restart” button and “Helpful Illustration” button. Then, I presented my work to my supervisors, Mr. Melvin, Miss Manggala and Miss June. Subsequently, I helped Miss Manggala in completing her engineering report on Business Line General Application (BLGA) products.
9 June 2010
I continued helping Miss Manggala on her report.
10 June 2010
I completed another engineering report Miss Manggala wanted me to help her with, which is to determine the optimum parameter setting for ADAT3 die bonding process for Bim16A on SOT363 products. For this feasibility report, I used Minitab to perform many simulations to determine the optimum set of parameters. Furthermore, I continued post project days by updating Product Master Data (PMD) as well as corresponding bonding diagrams on the intranet.
11 June 2010
Today, I updated some bonding diagrams. These bonding diagrams that I had updated are meant for new products which are just introduced. Besides that, I also helped Miss Manggala on another engineering report, which is aimed to determine the optimum process parameters for PHICOM3 24k wire bonding machine using 50um diameter gold wire.
Tuesday, June 8, 2010
7 June 2010
I spent all the day writing Excel codes to produce a comprehensive set of Macros. I had successfully annexed a few additional features into the earlier version. For instance, comments will be shown if certain results are calculated. I had also provided prospective users with helpful illustrations that will boost their understanding of the parameters that they need to insert. These diagrams can also be prompted out if the user intends to look at them after all the calculation results are displayed. Furthermore, this program comes with an embedded feature that will clear all contents in that active Excel sheet whenever the “Start/Restart” button is clicked.
Friday, June 4, 2010
1-4 June 2010
I was admitted to hospital for these 4 days as I re-injured my vulnerable back. I was and still am suffering from slipped discs, solidified discs and inflamed nerves, all around lumbar of the body.
31 May 2010
After much research into the subject of Macros, I was able to come up with a sequence of programming codes that will extract as well as show inputs provided by the user, perform calculations on those values and generate those arithmetic results. That sequence of codes that I had created basically covered all the theoretical evaluation part of the project that I had already completed, which is the feasibility of implementing upbent lead frames for SOT363F products. It proved to be a success as the string of results generated based of the same set of parameters considered for my project are exactly the same as those obtained by my hand calculations which are showed coherently in my project report. Nonetheless, I did not dwell on that success and strive to refine and add more features to my Excel program such as pop-up diagrams accompanying prompt input box to enhance user’s understanding of the value being referred to. Besides that, I am also working on providing additional comments on results generated. For instance, if the distance between the capillary and the die is less than zero, a message of “cracked die” will be shown.
Thursday, May 27, 2010
21 - 27 May 2010
21 May 2010
I continued my quest in producing a comprehensive report on the feasibility of using upbent lead frames for SOT363F products. In the mean time, I was given a side chore to complete which was to update the Product Master Data (PMD).
24 May 2010
I had completed my project report on the feasibility of using upbent lead frames for SOT363F products. It is 58 pages long. I know quantity is not always commensurable with quality. Nonetheless, I would endeavor to debunk that as I had placed profound effort in conjuring up this report. Through this time-consuming process, I had assiduously undergone theoretical evaluation of the problem at hand; acquire actual values on actual products and finally simulating obtained data using software called Minitab. Besides that, I had enhanced my skills of writing an engineering report as well as significantly improved my Microsoft Word and Excel literacy.
In addition to project report, I spent the rest of the day updating Product Master Data (PMD) as well as detecting and correcting errors found in PMD updated by colleagues.
25 May 2010
I started off the day updating Product Master Data (PMD), before proceeding to take quite a number of pictures on decapped products, both top view and side view. Moreover, I also took pictures on die pushed products.
26 May 2010
I spent the whole day gaining cognizance about Macros, which is one of the most powerful features in Microsoft Excel. I was given a book to read. The objective of using Macros is to ease our works and shorten task completion time. I was asked to create Macros akin to the project that I had just completed so that whenever there is another pristine set of parameters to be evaluated, one does not need to come through all those tedious processes like calculations, actual value acquisition and Minitab simulations, to have a rough overview on the feasibility of implementing that set of parameters.
27 May 2010
I proceeded with my effort to engender Macros. I had decided to use divide and conquer strategy in coming up with usable Macros by dividing the whole project into noticeable parts and writing Macros for each one.
Besides that, I was requested by Miss Manggala to aid her in completing her engineering report. To accomplish that, I was required to use JMP software to simulate over five thousand values obtained from the back end testing, in order to produce multiple relevant graphs impregnating process stability. I was also required to tag along Puan Norham who was in charge of performing manual tests on failed products to authenticate that the products were indeed flawed, and were not due to machine malfunctioning.
I continued my quest in producing a comprehensive report on the feasibility of using upbent lead frames for SOT363F products. In the mean time, I was given a side chore to complete which was to update the Product Master Data (PMD).
24 May 2010
I had completed my project report on the feasibility of using upbent lead frames for SOT363F products. It is 58 pages long. I know quantity is not always commensurable with quality. Nonetheless, I would endeavor to debunk that as I had placed profound effort in conjuring up this report. Through this time-consuming process, I had assiduously undergone theoretical evaluation of the problem at hand; acquire actual values on actual products and finally simulating obtained data using software called Minitab. Besides that, I had enhanced my skills of writing an engineering report as well as significantly improved my Microsoft Word and Excel literacy.
In addition to project report, I spent the rest of the day updating Product Master Data (PMD) as well as detecting and correcting errors found in PMD updated by colleagues.
25 May 2010
I started off the day updating Product Master Data (PMD), before proceeding to take quite a number of pictures on decapped products, both top view and side view. Moreover, I also took pictures on die pushed products.
26 May 2010
I spent the whole day gaining cognizance about Macros, which is one of the most powerful features in Microsoft Excel. I was given a book to read. The objective of using Macros is to ease our works and shorten task completion time. I was asked to create Macros akin to the project that I had just completed so that whenever there is another pristine set of parameters to be evaluated, one does not need to come through all those tedious processes like calculations, actual value acquisition and Minitab simulations, to have a rough overview on the feasibility of implementing that set of parameters.
27 May 2010
I proceeded with my effort to engender Macros. I had decided to use divide and conquer strategy in coming up with usable Macros by dividing the whole project into noticeable parts and writing Macros for each one.
Besides that, I was requested by Miss Manggala to aid her in completing her engineering report. To accomplish that, I was required to use JMP software to simulate over five thousand values obtained from the back end testing, in order to produce multiple relevant graphs impregnating process stability. I was also required to tag along Puan Norham who was in charge of performing manual tests on failed products to authenticate that the products were indeed flawed, and were not due to machine malfunctioning.
Thursday, May 20, 2010
17 - 20 May 2010
17 May 2010
I continued my exhilarating odyssey into the world of calculation. Today, I finished calculating the theoretical distance between capillary and the die under ideal die placement as well as under worst case scenario. By ideal die placement, the die is perfectly situated at the centre of the major flag. On the other hand, worst case scenario infers that the die is displaced 20um.
Next, I calculated the distance between die edge and wire, stretching from the line of ball bond on the die. Again, two situations are considered, that are ideal die placement as well as worst case scenario.
I finished off the day by evaluating the displacement area of wedge bond on minor lead. I took the center placement of the wedge, which is the ideal case as a reference point. Subsequently, I modeled each displacement as a circle centered about that reference point.
All calculations will be shown.
18 May 2010
I spent the day tabulating and simulating those data I had obtained from the assembly line into Minitab. This is a software that can depict many parameters akin to any process under inspection. With the helpful Miss June beside me, I was able to simulate, understand and encapsulate the graphs as well as information generated. To put it compendiously, the processes that I had been involved in are stable.
Besides Minitab, I also calculated the maximum distance that the die can deviate vertically before hitting the capillary. Again, all calculations will be shown.
19 May 2010
I had basically finish all the data acquisition as well as theoretical calculations relevant to my project. I was asked to detect errors in the method used by Miss June in calculating those similar parameters that I had calculated. After some meticulous inspection, I was able to detect some errors and remedied them. I spent the rest of the day gaining knowledge on how to conjure up a report regarding my project. I was given several reading materials to attain adequate information deemed relevant to producing an engineering technical report.
20 May 2010
My agenda today was indubitably to produce a quality report. I gained several skills dealing with graphics in Microsoft Word in my quest to engender a splendid report.
I continued my exhilarating odyssey into the world of calculation. Today, I finished calculating the theoretical distance between capillary and the die under ideal die placement as well as under worst case scenario. By ideal die placement, the die is perfectly situated at the centre of the major flag. On the other hand, worst case scenario infers that the die is displaced 20um.
Next, I calculated the distance between die edge and wire, stretching from the line of ball bond on the die. Again, two situations are considered, that are ideal die placement as well as worst case scenario.
I finished off the day by evaluating the displacement area of wedge bond on minor lead. I took the center placement of the wedge, which is the ideal case as a reference point. Subsequently, I modeled each displacement as a circle centered about that reference point.
All calculations will be shown.
18 May 2010
I spent the day tabulating and simulating those data I had obtained from the assembly line into Minitab. This is a software that can depict many parameters akin to any process under inspection. With the helpful Miss June beside me, I was able to simulate, understand and encapsulate the graphs as well as information generated. To put it compendiously, the processes that I had been involved in are stable.
Besides Minitab, I also calculated the maximum distance that the die can deviate vertically before hitting the capillary. Again, all calculations will be shown.
19 May 2010
I had basically finish all the data acquisition as well as theoretical calculations relevant to my project. I was asked to detect errors in the method used by Miss June in calculating those similar parameters that I had calculated. After some meticulous inspection, I was able to detect some errors and remedied them. I spent the rest of the day gaining knowledge on how to conjure up a report regarding my project. I was given several reading materials to attain adequate information deemed relevant to producing an engineering technical report.
20 May 2010
My agenda today was indubitably to produce a quality report. I gained several skills dealing with graphics in Microsoft Word in my quest to engender a splendid report.
17 - 20 May 2010
17 May 2010
I continued my exhilarating odyssey into the world of calculation. Today, I finished calculating the theoretical distance between capillary and the die under ideal die placement as well as under worst case scenario. By ideal die placement, the die is perfectly situated at the centre of the major flag. On the other hand, worst case scenario infers that the die is displaced 20um.
Next, I calculated the distance between die edge and wire, stretching from the line of ball bond on the die. Again, two situations are considered, that are ideal die placement as well as worst case scenario.
I finished off the day by evaluating the displacement area of wedge bond on minor lead. I took the center placement of the wedge, which is the ideal case as a reference point. Subsequently, I modeled each displacement as a circle centered about that reference point.
All calculations will be shown.
18 May 2010
I spent the day tabulating and simulating those data I had obtained from the assembly line into Minitab. This is a software that can depict many parameters akin to any process under inspection. With the helpful Miss June beside me, I was able to simulate, understand and encapsulate the graphs as well as information generated. To put it compendiously, the processes that I had been involved in are stable.
Besides Minitab, I also calculated the maximum distance that the die can deviate vertically before hitting the capillary. Again, all calculations will be shown.
19 May 2010
I had basically finish all the data acquisition as well as theoretical calculations relevant to my project. I was asked to detect errors in the method used by Miss June in calculating those similar parameters that I had calculated. After some meticulous inspection, I was able to detect some errors and remedied them. I spent the rest of the day gaining knowledge on how to conjure up a report regarding my project. I was given several reading materials to attain adequate information deemed relevant to producing an engineering technical report.
20 May 2010
My agenda today was indubitably to produce a quality report. I gained several skills dealing with graphics in Microsoft Word in my quest to engender a splendid report.
I continued my exhilarating odyssey into the world of calculation. Today, I finished calculating the theoretical distance between capillary and the die under ideal die placement as well as under worst case scenario. By ideal die placement, the die is perfectly situated at the centre of the major flag. On the other hand, worst case scenario infers that the die is displaced 20um.
Next, I calculated the distance between die edge and wire, stretching from the line of ball bond on the die. Again, two situations are considered, that are ideal die placement as well as worst case scenario.
I finished off the day by evaluating the displacement area of wedge bond on minor lead. I took the center placement of the wedge, which is the ideal case as a reference point. Subsequently, I modeled each displacement as a circle centered about that reference point.
All calculations will be shown.
18 May 2010
I spent the day tabulating and simulating those data I had obtained from the assembly line into Minitab. This is a software that can depict many parameters akin to any process under inspection. With the helpful Miss June beside me, I was able to simulate, understand and encapsulate the graphs as well as information generated. To put it compendiously, the processes that I had been involved in are stable.
Besides Minitab, I also calculated the maximum distance that the die can deviate vertically before hitting the capillary. Again, all calculations will be shown.
19 May 2010
I had basically finish all the data acquisition as well as theoretical calculations relevant to my project. I was asked to detect errors in the method used by Miss June in calculating those similar parameters that I had calculated. After some meticulous inspection, I was able to detect some errors and remedied them. I spent the rest of the day gaining knowledge on how to conjure up a report regarding my project. I was given several reading materials to attain adequate information deemed relevant to producing an engineering technical report.
20 May 2010
My agenda today was indubitably to produce a quality report. I gained several skills dealing with graphics in Microsoft Word in my quest to engender a splendid report.
Friday, May 14, 2010
11-14 May 2010
11 May 2010
Today, I gained a better understanding of the operation as well as errors akin to ADAT and PHICOM machines. First off, I observed how a technician attended to “Post Bond Total Skip Count Exceeded” error on an ADAT machine. Initial comprehension was that presence of tilted dies were detected, which rendered the PRS image darker than usual. The technician once thought it was just sporadic occurrence; however, subsequent series of same errors faulted his initial judgment. He then discovered that the push up needle was rickety and promptly replaced it with a new one. Push up needle serves the purpose of pushing up the designated die to be picked up by the collet.
Next, still within the vicinity of ADAT machines, I came across “Touchdown Push Up Too Soon” error. This means that the push up needle elevated the die too soon for the collet to pick up. The operator attended the problem by changing the process delay value.
Mr. Leong provided me with several additions to my knowledge of ADAT as well as die bonding process. He taught me that there the first die attach machine was invented by the Germans. Predictably, it was slow. Then, we have ADAT1, ADAT2 and ADAT3. For ADAT2, there are 3 different types: ADAT2 12k, ADAT2 14k, ADAT2 18k, with the last type being the fastest among the three. So, the notation of 12k, 14k and 18k simply impregnates the idea of different speed. Apart from that, Mr. Leong also talked about what SOT and SOD mean. SOT is the acronym for Small Outline Transistor, while SOD means Small Outline Diode. Furthermore, the helpful Mr. Leong told me that RF (Radio Frequency) products are relatively costlier as more convoluted process is implicated in which wafer back coat is required. Wafer back coating is similar to glue bonding.
Next on the agenda are errors associated with PHICOM wire bonding machines. When one encounters “Total Skipcount Exceeded” error, it probably indicates that the predetermined allowable number of units that are devoid of dies or “Total Skip Setting” value was reached or exceeded. There is always a “Skip Counter” indicator beside the “Total Skip Setting” to tell us about how many units have been skipped by the machine. Another setting worthy of mentioning is “Sequential Skip Setting” which is similar to “Total Skip Setting” except that it indicates the number of acceptable consecutive defective units to be skipped. Besides that, when the error “Spark Not Completed” pops out, it means that spark is not provided for wire bonding process, culminating in the failure to form Free Air Ball (FAB).
In addition, I also tried my hands on die shear. Previously, I had been performing ball shear. After several runs with ball shear, I can deem myself as an expert in ball shear. However, the same cannot be said to die shear. The first thought that came to mind was that it would just be a piece of cake. It turned out to be an exhilarating experience though it was tremendously difficult. In the process, I managed to obliterate many dies. Poor dies, rest in peace…
12 May 2010
Today was really a humdinger as I was assigned something totally different and challenging. Before I go into details of what I was asked to do, Miss June briefed me about the upcoming production of a new product which is based on upbent lead frames, which have the major as well as minor bond pads elevated slightly. Customarily, lead frames are completely flat. Miss June’s briefing was rather vague and convoluted which culminated in me enveloping in a mist of uncertainty and questions.
Uncertainty notwithstanding, after being provided with relevant information, I proceeded to calculate the length of that bent portion. Subsequently, with that aforementioned value in mind, I calculated the angle of bending. After obtaining those theoretical values, I went into the assembly line where I performed several measurements to acquire some practical values, in order to vindicate my theoretical findings. Fortunately, the values obtained theoretically and practically were coterminous at worst and exactly the same at best.
Next, I moved on to calculate the angle of R35 capillary tip. Before I could attain that, I did some concise research on the parts of the R35 wire bonding capillary, and understanding the parameters or dimensions involved. Based on the Outer Diameter (OD), Length (L), Cone Angle (CA), I was able to determine the outer angle of R35 capillary tip as well as the cone vertical height.
Moving on, I evaluated the remaining space available when a flat lead frame is to be used upbent. With that in mind, and information regarding die size, I also determined the final remaining space available after the die is attached to the bond pad. After that, I went into the assembly line again to measure the major and minor bond pad length.
13 May 2010
I continued where I left off yesterday, performing measurements of major as well as minor flags length. I was able to finish the measurements of three distinct lead frames, which are designated for SOT343F, SOT343R2 and SOT363F. Also, I finished measuring the bending angle and the bending base length of SOT343F and SOT363F lead frames. The same cannot be performed on SOT343R2 lead frames as this type of lead frame is not upbent. After lunch, I continued my unique relationship with the measurement device as I was assigned to perform 360 measurements in order to determine ADAT and PHICOM consistency. All of these are part of the challenging assignment given to me yesterday.
14 May 2010
I tabulated all the data I acquired in the past two days. For the 360 measurements involving horizontal and vertical distances from my designated reference point on the major flag to the die as well as from a designated reference point on the minor lead to the wedge bond, I also calculated the hypotenuse distance in order to determine the consistency of ADAT and PHICOM machines. For the machines to be regarded as consistent, the standard deviation is to be less than 10µm, which is rightly so for both ADAT as well as PHICOM machine.
While waiting for Miss June to assign me with further tasks, I spent my time taking images of die pushed units. Similar to die shear units, the die on each individual unit is removed by force. For die shear products, the die is removed by machine, however, for die push units; the die is removed by tweezers held by human fingers.
After lunch, after lucid explanations from Miss June, I began the intriguing calculation of the possibility of capillary hitting the die. To show this, I needed to calculate the distance between the capillary and the die during wire bonding process. I considered the ideal case, where the die is situated at the middle of the major flag, as well as the worst case scenario, in which the die is displaced for 20µm. This maximum displacement value is calculated by evaluating the process capability index of 4σ.
I will upload all the photos pertaining to the calculations that I had done when I gain internet access again. For your information, my home is without internet for one month. I know, it is agonizing. That is why I could only update my blog so sporadically
Today, I gained a better understanding of the operation as well as errors akin to ADAT and PHICOM machines. First off, I observed how a technician attended to “Post Bond Total Skip Count Exceeded” error on an ADAT machine. Initial comprehension was that presence of tilted dies were detected, which rendered the PRS image darker than usual. The technician once thought it was just sporadic occurrence; however, subsequent series of same errors faulted his initial judgment. He then discovered that the push up needle was rickety and promptly replaced it with a new one. Push up needle serves the purpose of pushing up the designated die to be picked up by the collet.
Next, still within the vicinity of ADAT machines, I came across “Touchdown Push Up Too Soon” error. This means that the push up needle elevated the die too soon for the collet to pick up. The operator attended the problem by changing the process delay value.
Mr. Leong provided me with several additions to my knowledge of ADAT as well as die bonding process. He taught me that there the first die attach machine was invented by the Germans. Predictably, it was slow. Then, we have ADAT1, ADAT2 and ADAT3. For ADAT2, there are 3 different types: ADAT2 12k, ADAT2 14k, ADAT2 18k, with the last type being the fastest among the three. So, the notation of 12k, 14k and 18k simply impregnates the idea of different speed. Apart from that, Mr. Leong also talked about what SOT and SOD mean. SOT is the acronym for Small Outline Transistor, while SOD means Small Outline Diode. Furthermore, the helpful Mr. Leong told me that RF (Radio Frequency) products are relatively costlier as more convoluted process is implicated in which wafer back coat is required. Wafer back coating is similar to glue bonding.
Next on the agenda are errors associated with PHICOM wire bonding machines. When one encounters “Total Skipcount Exceeded” error, it probably indicates that the predetermined allowable number of units that are devoid of dies or “Total Skip Setting” value was reached or exceeded. There is always a “Skip Counter” indicator beside the “Total Skip Setting” to tell us about how many units have been skipped by the machine. Another setting worthy of mentioning is “Sequential Skip Setting” which is similar to “Total Skip Setting” except that it indicates the number of acceptable consecutive defective units to be skipped. Besides that, when the error “Spark Not Completed” pops out, it means that spark is not provided for wire bonding process, culminating in the failure to form Free Air Ball (FAB).
In addition, I also tried my hands on die shear. Previously, I had been performing ball shear. After several runs with ball shear, I can deem myself as an expert in ball shear. However, the same cannot be said to die shear. The first thought that came to mind was that it would just be a piece of cake. It turned out to be an exhilarating experience though it was tremendously difficult. In the process, I managed to obliterate many dies. Poor dies, rest in peace…
12 May 2010
Today was really a humdinger as I was assigned something totally different and challenging. Before I go into details of what I was asked to do, Miss June briefed me about the upcoming production of a new product which is based on upbent lead frames, which have the major as well as minor bond pads elevated slightly. Customarily, lead frames are completely flat. Miss June’s briefing was rather vague and convoluted which culminated in me enveloping in a mist of uncertainty and questions.
Uncertainty notwithstanding, after being provided with relevant information, I proceeded to calculate the length of that bent portion. Subsequently, with that aforementioned value in mind, I calculated the angle of bending. After obtaining those theoretical values, I went into the assembly line where I performed several measurements to acquire some practical values, in order to vindicate my theoretical findings. Fortunately, the values obtained theoretically and practically were coterminous at worst and exactly the same at best.
Next, I moved on to calculate the angle of R35 capillary tip. Before I could attain that, I did some concise research on the parts of the R35 wire bonding capillary, and understanding the parameters or dimensions involved. Based on the Outer Diameter (OD), Length (L), Cone Angle (CA), I was able to determine the outer angle of R35 capillary tip as well as the cone vertical height.
Moving on, I evaluated the remaining space available when a flat lead frame is to be used upbent. With that in mind, and information regarding die size, I also determined the final remaining space available after the die is attached to the bond pad. After that, I went into the assembly line again to measure the major and minor bond pad length.
13 May 2010
I continued where I left off yesterday, performing measurements of major as well as minor flags length. I was able to finish the measurements of three distinct lead frames, which are designated for SOT343F, SOT343R2 and SOT363F. Also, I finished measuring the bending angle and the bending base length of SOT343F and SOT363F lead frames. The same cannot be performed on SOT343R2 lead frames as this type of lead frame is not upbent. After lunch, I continued my unique relationship with the measurement device as I was assigned to perform 360 measurements in order to determine ADAT and PHICOM consistency. All of these are part of the challenging assignment given to me yesterday.
14 May 2010
I tabulated all the data I acquired in the past two days. For the 360 measurements involving horizontal and vertical distances from my designated reference point on the major flag to the die as well as from a designated reference point on the minor lead to the wedge bond, I also calculated the hypotenuse distance in order to determine the consistency of ADAT and PHICOM machines. For the machines to be regarded as consistent, the standard deviation is to be less than 10µm, which is rightly so for both ADAT as well as PHICOM machine.
While waiting for Miss June to assign me with further tasks, I spent my time taking images of die pushed units. Similar to die shear units, the die on each individual unit is removed by force. For die shear products, the die is removed by machine, however, for die push units; the die is removed by tweezers held by human fingers.
After lunch, after lucid explanations from Miss June, I began the intriguing calculation of the possibility of capillary hitting the die. To show this, I needed to calculate the distance between the capillary and the die during wire bonding process. I considered the ideal case, where the die is situated at the middle of the major flag, as well as the worst case scenario, in which the die is displaced for 20µm. This maximum displacement value is calculated by evaluating the process capability index of 4σ.
I will upload all the photos pertaining to the calculations that I had done when I gain internet access again. For your information, my home is without internet for one month. I know, it is agonizing. That is why I could only update my blog so sporadically
Monday, May 10, 2010
10 May 2010
I started off the day by gaining cognizance about the term “partial wafer”. Partial wafer is exactly the same as ordinary wafer except that only a certain amount of dies from a partial wafer will be used or picked up during production. That amount will be dependent upon customers’ demands. After a designated amount of dies had been picked up, that wafer will be kept for further use.
Besides that, I went to the front end where Mr. Leong is stationed. He was monitoring the production of a new product. An ineluctable predicament surfaced in the form of the absence of numbering of die pick up starting position. To rub salt on wound, some of the dies in propinquity of the edges were not entirely defective. This will pose some impediment to the effectiveness of the Pattern Recognition System (PRS) in identifying good (usable) dies. After numerous attempts, the indefatigable spirit of Mr. Leong prevailed as he successfully estimated a proper starting position by trial and error.
Mr. Leong also taught me that the Pattern Recognition System (PRS) of ADAT2 die bonding machine works on the principle of binary scale. In other words, it discerns patterns based on black and white images of the die. On the other hand, PRS of ADAT3 machine not only works on binary scale, but also grayscale. This renders the PRS of ADAT3 machine significantly efficacious than ADAT2 machine. Nonetheless, higher cost of ADAT3 machine prevents its widespread use.
My learning experience continued after lunch break. After the front end process, the die bonded as well as wire bonded lead frames will be channeled to the mid-end process. Before that transfer takes place, unusual lead frames will be identified using stickers with different colours to inform personnel in mid end. Firstly, red coloured sticker indicates that certain part of the lead frames contain new device or new lot. Within front end itself, lead frames having new device will be noted with pen marking on lead frames to avert or assuage mixed device possibility. Next, green coloured sticker is used when a portion of the lead frames is unwanted scrap of production. Lastly, blue coloured sticker is used to represent lead frames that had been welded. Welded parts may be uneven and therefore it is not advisable to mold them.
During a casual stroll around front end, I came across several customer complaints. A customer from Korea complained about partial lifted ball bond. The cause of this is believed to be floating of lead frames due to copper build-up at heater block. During wire bonding process, as the capillary exerts lateral force on the ball at the bondpad, the force will not be spread evenly. Next, a Dutch company complained about offset ball bond, which means that the balls bonded on dies are out of designated positions. Thorough investigation reveals that the probable cause is the failure during Pattern Recognition System (PRS) after lamp burnt (dark field) incident.
Circular pulley-like parts are ubiquitous between each machine. According to Mr. Leong, this is meant to provide operators with more time to troubleshoot and amend errors in case of machine breakdown. During that time, other functional, parallel machines can continue production using inputs stored or winded on the pulleys.
Besides that, I went to the front end where Mr. Leong is stationed. He was monitoring the production of a new product. An ineluctable predicament surfaced in the form of the absence of numbering of die pick up starting position. To rub salt on wound, some of the dies in propinquity of the edges were not entirely defective. This will pose some impediment to the effectiveness of the Pattern Recognition System (PRS) in identifying good (usable) dies. After numerous attempts, the indefatigable spirit of Mr. Leong prevailed as he successfully estimated a proper starting position by trial and error.
Mr. Leong also taught me that the Pattern Recognition System (PRS) of ADAT2 die bonding machine works on the principle of binary scale. In other words, it discerns patterns based on black and white images of the die. On the other hand, PRS of ADAT3 machine not only works on binary scale, but also grayscale. This renders the PRS of ADAT3 machine significantly efficacious than ADAT2 machine. Nonetheless, higher cost of ADAT3 machine prevents its widespread use.
My learning experience continued after lunch break. After the front end process, the die bonded as well as wire bonded lead frames will be channeled to the mid-end process. Before that transfer takes place, unusual lead frames will be identified using stickers with different colours to inform personnel in mid end. Firstly, red coloured sticker indicates that certain part of the lead frames contain new device or new lot. Within front end itself, lead frames having new device will be noted with pen marking on lead frames to avert or assuage mixed device possibility. Next, green coloured sticker is used when a portion of the lead frames is unwanted scrap of production. Lastly, blue coloured sticker is used to represent lead frames that had been welded. Welded parts may be uneven and therefore it is not advisable to mold them.
During a casual stroll around front end, I came across several customer complaints. A customer from Korea complained about partial lifted ball bond. The cause of this is believed to be floating of lead frames due to copper build-up at heater block. During wire bonding process, as the capillary exerts lateral force on the ball at the bondpad, the force will not be spread evenly. Next, a Dutch company complained about offset ball bond, which means that the balls bonded on dies are out of designated positions. Thorough investigation reveals that the probable cause is the failure during Pattern Recognition System (PRS) after lamp burnt (dark field) incident.
Circular pulley-like parts are ubiquitous between each machine. According to Mr. Leong, this is meant to provide operators with more time to troubleshoot and amend errors in case of machine breakdown. During that time, other functional, parallel machines can continue production using inputs stored or winded on the pulleys.
Sunday, May 9, 2010
7 May 2010
I gained a deeper understanding on the wafer sawing process and the corresponding machines involved. First off, I noticed that the amount of wafer sawing machine is considerably more than that of wafer washer machine. After some lucid explanations from Miss Manggala, this is because one wafer washer can be shared by several wafer sawing machines as the washing process is a brief process. In a wafer washer machine, water is shot at high velocity at sawn wafer which is rotated swiftly. Although such conditions may seem to be destructive to the dies, the dies are actually unaffected! However, if we were to touch the surface of the wafer, though this condition seems to be less extreme than the previous instance, the dies will be damaged by our electrostatic charge as well as oxidation.
Next, in each wafer sawing machine, chemicals are used to clean impurities on the wafer surface. When the sawing blade is blunt or different blade is needed, the suitable blade will be changed manually by operators. After the new blade is installed, a dummy wafer is used for blade dressing. In other words, it means blade seasoning or to smoothen the blade edge. If this step is neglected, wafer sawn would have cracked dies.
After the sawing process, as I had mentioned earlier, wafer washing ensues. Then, that piece of wafer will be stored in cupboards. These cupboards are annexed with gas hose that channels nitrogen gas into the cupboards which can prevent oxidation of dies.
Oh! Ya! How can I not talk about the irksome bonding diagrams? I managed to complete the re-updating of SOT457P and SOT753P bonding diagrams.
Next, in each wafer sawing machine, chemicals are used to clean impurities on the wafer surface. When the sawing blade is blunt or different blade is needed, the suitable blade will be changed manually by operators. After the new blade is installed, a dummy wafer is used for blade dressing. In other words, it means blade seasoning or to smoothen the blade edge. If this step is neglected, wafer sawn would have cracked dies.
After the sawing process, as I had mentioned earlier, wafer washing ensues. Then, that piece of wafer will be stored in cupboards. These cupboards are annexed with gas hose that channels nitrogen gas into the cupboards which can prevent oxidation of dies.
Oh! Ya! How can I not talk about the irksome bonding diagrams? I managed to complete the re-updating of SOT457P and SOT753P bonding diagrams.
Thursday, May 6, 2010
5-6 May 2010
5 May 2010
It looks like my time here in NXP Semiconductor is preordained to be filled with a deluge of bonding diagrams. After completing 1119 bonding diagrams, with each consuming up to 5 minutes to complete, I was again assigned the unenviable task of updating bonding diagrams. I was ordered to add details, make circumlocutory resize actions on pictures and other petty stuffs. I was able to finish re-updating SOT346 (SC59), SOT323 (SC70), SOT457 (SC74) and SOT457P bonding diagrams which involved adding the notation “1 die size” as well as adding information table. My day just couldn’t get any worse. I was again asked to refine SOT353P, SOT363P, SOT457P and SOT753P bonding diagrams by adding yellow colour to highlight package, family and crystal information, as well as expanding ball size, subsequently centralizing them. It was an unimpeachable waste of my time! The only thing I learned is to suppress my anguish and tried not to be too antagonized.
6 May 2010
Nothing learned today. I finished re-updating SOT353P and SOT363P bonding diagrams amid utmost exasperation and frustration.
It looks like my time here in NXP Semiconductor is preordained to be filled with a deluge of bonding diagrams. After completing 1119 bonding diagrams, with each consuming up to 5 minutes to complete, I was again assigned the unenviable task of updating bonding diagrams. I was ordered to add details, make circumlocutory resize actions on pictures and other petty stuffs. I was able to finish re-updating SOT346 (SC59), SOT323 (SC70), SOT457 (SC74) and SOT457P bonding diagrams which involved adding the notation “1 die size” as well as adding information table. My day just couldn’t get any worse. I was again asked to refine SOT353P, SOT363P, SOT457P and SOT753P bonding diagrams by adding yellow colour to highlight package, family and crystal information, as well as expanding ball size, subsequently centralizing them. It was an unimpeachable waste of my time! The only thing I learned is to suppress my anguish and tried not to be too antagonized.
6 May 2010
Nothing learned today. I finished re-updating SOT353P and SOT363P bonding diagrams amid utmost exasperation and frustration.
Tuesday, May 4, 2010
3-4 May 2010
3 May 2010
I continued my nexus with bonding diagrams. I was given 4 new packages to update today, SOT23, SOT343, SOT343F and SOT346 (SC59). I was able to finish all of them before lunch break. The following is the comprehensive lowdown of the packages and the corresponding amount of bonding diagrams that I had done.
After lunch, I went to the line with Miss Norham. To be more specific, we went to the back end portion of the line. While waiting for our turn to perform tests on products, she mentioned that there are currently four companies supplying lead frames to NXP Semiconductor. They are Sumitomo, Enomoto, Possehl and Jade. The test that she intended to perform was to gain cognizance of the feasibility of using Possehl lead frames for production purpose for a particular device. To put it compendiously, she will put the trimmed and formed units using current production lead frame as well as those using Possehl lead frames into NT16 machine, to garner results or summary regarding the number of functional and substandard devices.
In NXP Semiconductor, as I had mentioned earlier during previous blog entries, there are two types of machines involved at the back end process. One being the IBE, and the other being NT16 or NX16 or TDD. When NT16/NX16/TDD comes into mind, ATF machine is indispensable. ATF stands for Auto Trim and Form. For more details on the differences in terms of operations between the two types, kindly refer to my previous blog entries. For this entry, I want to elaborate on the advantage of NT16/NX16/TDD over IBE. Firstly, NT15/NX16/TDD is faster and can be used for matrix as well as bi lead frames. IBE on the other hand, can only be used for bi lead frames. In addition, another difference between the two types of machine is that one PARSET is needed for an IBE, while a number of NT16/NX16/TDD can share a same PARSET. PARSET can be deemed as the repository of the information and operations for carrying out acceptance test (AT) and final test (FT). For further information on AT and FT, please refer to the following paragraphs.
From my observation as well as from the explanations provided by Miss Norham, for NT16/NX16/TDD, trimmed and formed units will be dumped into a rotating, vibrating bowl, where the units will be subsequently fed to a linear track. Here, there are sensors to sense the presence of units. Next, the units will go through a position sensor that indicates whether the units are oriented correctly or otherwise. Those units with wrong orientation will be corrected in the rotary portion. Then, the units will undergo final test (FT) to be followed by acceptance test (AT).
Besides that, there are two tests generally performed. The first being the final test (FT), and the other being the acceptance test (AT). Both are coterminous. Nonetheless, final test entails stricter or more rigorous test limits. Final test specifications are set by us, while acceptance test vicariously mirror what our customers want. Moving on with the similarities, both tests involve copious test specifications. For instance, akelvin and fkelvin. Notice that the first letter is the only discrepancy. The letter “a” refers to acceptance test, while the letter “f” indicates final test. Those units that failed either akelvin or fkelvin are regarded as units that may have missing legs or contacts, bent legs such that the clamper part of the test machine is not able to clamp the unit legs properly. If there were to be excessive amount of failed units under akelvin or fkelvin, the clamper contacts may be filthy. Next, I encountered units failing open test. These units may be devoid of dies (dummies), wires or have edge dies. Moving on, short test reveals units that have wires short circuited. Moreover, dvth and avth tests present us with a notion that units failing these tests may have flawed die attachments. Failed units of the respective tests will be guided into designated bins where they can be collected for further tests.
Lastly, I learnt about the meanings behind the notation used in marking each unit.
4 May 2010
What I did for today were just repetition of the things I had done before. Someone please succour me away from this purgatory. It is slowing emasculating my brain power as the things I am doing are just repetitive in nature. An overview of what I had done: Wafer inspection, updating of company’s Product Master Data (PMD) and acquisition of images using high power scope. The subjects of image acquisition are die sheared lead frames. Die sheared lead frames mean that the dies that were attached to the bondpads on lead frames were pushed away in a process known as die shear to evaluate the strength of the die bonding.
I continued my nexus with bonding diagrams. I was given 4 new packages to update today, SOT23, SOT343, SOT343F and SOT346 (SC59). I was able to finish all of them before lunch break. The following is the comprehensive lowdown of the packages and the corresponding amount of bonding diagrams that I had done.
After lunch, I went to the line with Miss Norham. To be more specific, we went to the back end portion of the line. While waiting for our turn to perform tests on products, she mentioned that there are currently four companies supplying lead frames to NXP Semiconductor. They are Sumitomo, Enomoto, Possehl and Jade. The test that she intended to perform was to gain cognizance of the feasibility of using Possehl lead frames for production purpose for a particular device. To put it compendiously, she will put the trimmed and formed units using current production lead frame as well as those using Possehl lead frames into NT16 machine, to garner results or summary regarding the number of functional and substandard devices.
In NXP Semiconductor, as I had mentioned earlier during previous blog entries, there are two types of machines involved at the back end process. One being the IBE, and the other being NT16 or NX16 or TDD. When NT16/NX16/TDD comes into mind, ATF machine is indispensable. ATF stands for Auto Trim and Form. For more details on the differences in terms of operations between the two types, kindly refer to my previous blog entries. For this entry, I want to elaborate on the advantage of NT16/NX16/TDD over IBE. Firstly, NT15/NX16/TDD is faster and can be used for matrix as well as bi lead frames. IBE on the other hand, can only be used for bi lead frames. In addition, another difference between the two types of machine is that one PARSET is needed for an IBE, while a number of NT16/NX16/TDD can share a same PARSET. PARSET can be deemed as the repository of the information and operations for carrying out acceptance test (AT) and final test (FT). For further information on AT and FT, please refer to the following paragraphs.
From my observation as well as from the explanations provided by Miss Norham, for NT16/NX16/TDD, trimmed and formed units will be dumped into a rotating, vibrating bowl, where the units will be subsequently fed to a linear track. Here, there are sensors to sense the presence of units. Next, the units will go through a position sensor that indicates whether the units are oriented correctly or otherwise. Those units with wrong orientation will be corrected in the rotary portion. Then, the units will undergo final test (FT) to be followed by acceptance test (AT).
Besides that, there are two tests generally performed. The first being the final test (FT), and the other being the acceptance test (AT). Both are coterminous. Nonetheless, final test entails stricter or more rigorous test limits. Final test specifications are set by us, while acceptance test vicariously mirror what our customers want. Moving on with the similarities, both tests involve copious test specifications. For instance, akelvin and fkelvin. Notice that the first letter is the only discrepancy. The letter “a” refers to acceptance test, while the letter “f” indicates final test. Those units that failed either akelvin or fkelvin are regarded as units that may have missing legs or contacts, bent legs such that the clamper part of the test machine is not able to clamp the unit legs properly. If there were to be excessive amount of failed units under akelvin or fkelvin, the clamper contacts may be filthy. Next, I encountered units failing open test. These units may be devoid of dies (dummies), wires or have edge dies. Moving on, short test reveals units that have wires short circuited. Moreover, dvth and avth tests present us with a notion that units failing these tests may have flawed die attachments. Failed units of the respective tests will be guided into designated bins where they can be collected for further tests.
Lastly, I learnt about the meanings behind the notation used in marking each unit.
4 May 2010
What I did for today were just repetition of the things I had done before. Someone please succour me away from this purgatory. It is slowing emasculating my brain power as the things I am doing are just repetitive in nature. An overview of what I had done: Wafer inspection, updating of company’s Product Master Data (PMD) and acquisition of images using high power scope. The subjects of image acquisition are die sheared lead frames. Die sheared lead frames mean that the dies that were attached to the bondpads on lead frames were pushed away in a process known as die shear to evaluate the strength of the die bonding.
Friday, April 30, 2010
29-30 April 2010
29 April 2010
I started off the day continuing my journey into a deeper cognizance of die bonding process. As we had seen yesterday, die bonding process involves die select, die pick-up, die transfer and die attach. The first two sub processes occur in the pick-up area, while the die attach sub process happens in the attach area. Die transfer takes place between the two areas. Naturally, these two areas need to be aligned to a common level. However, there is always a tolerance. The acceptable height difference between the areas is designated at 100µm. If the pick up area is higher than the attach area, machine speed will plummet due to prolonged travel time. On the other hand, if the attach area is higher than the pick up area, the propensity of the transfer arm to prang into the heater block cover will increase drastically.
As we all know, there are copious die sizes. Hence, different collets with the suitable size corresponding to the type of die handled are required. With that information in mind, I helped Miss Manggala to complete a subservient task, which was to check for any die sizes of package SOT363/SC88, from the intranet, which were not listed in a table of die dimensions that NXP Semiconductor is currently having. She will then need to make the purchase of those collets.
After completing the task, I proceeded to gain a deeper understanding of wire bonding process. First off, I stumbled upon what PHICOM really means. It is actually the acronym for Philips Computer. PHICOM machine is meant for wire bonding process. Generally, six steps are involved. I will provide the steps with the aid of the following pictures.
1) The capillary is moving from the spark to ball bond position. When the Free Air Ball (FAB) touches the die, which is also known as touchdown, the ball bonding process starts. Note that FAB is bonded on the die at elevated temperature, pressure and ultrasonic energy.
2) After bonding the ball, capillary makes the wire loop.
3) The capillary lands on the lead and wedge bonding process starts.
4) The capillary moves up. Next, wire-clamp is closed. The capillary moves further up to break the wire and thus from the tail (wedge).
5) As the wire reaches spark height, a tail is hanging under the capillary.
6) A spark forms a ball at the end of the wire. The wire-clamp opens and the air jet pulls the ball inside the capillary.
If you were heedful when reading the steps aforementioned, you would wonder, what is the purpose of ultrasonic energy? Actually, it serves as an avenue to wipe away oxides or undesirable contaminations on the contact area. Also, it helps to mature the bonding in combination with thermal energy. In other words, this insinuates that the ball bonding process can be carried out in a higher temperature. In addition, the presence of ultrasonic energy can soften the metal of Free Air Ball, thus rendering easier ball bonding process.
Apart from that, I had learnt that the difference between normal, reserve and trapezoid loop is the wire loop length. Besides, I got myself a fun fact too! Do you know that the melting point of gold is 1064°C? Oh! By the way, gold wire is the only material used for wire bonding.
I realized that the insipidity of this industrial training had returned when I was again ordered to update bonding diagrams. Now for SC88 package. Again, due to my fast execution, I was able to finish it by today.
30 April 2010
Mundane, sedentary nature of work is fast becoming an idiosyncratic aspect of my industrial training. Sporadic clandestine self permitted time off from facing the computer proved to be the only humdinger of my industrial training life. I started off the day doing again petty task, which is to tabulate the values I obtained from previous measurements into Microsoft Excel. As an overview, I tabulated ball diameter, ball height, wire pull, break point, ball shear as well as free air ball.
Next, try guessing what I was assigned to do. It was none other than the exasperating bonding diagrams!! I was given new package to update, namely SC70 and SC75. At the end of the day, I was able to complete them. I even had the luxury of calculating the bonding diagrams that I had done so far.
I started off the day continuing my journey into a deeper cognizance of die bonding process. As we had seen yesterday, die bonding process involves die select, die pick-up, die transfer and die attach. The first two sub processes occur in the pick-up area, while the die attach sub process happens in the attach area. Die transfer takes place between the two areas. Naturally, these two areas need to be aligned to a common level. However, there is always a tolerance. The acceptable height difference between the areas is designated at 100µm. If the pick up area is higher than the attach area, machine speed will plummet due to prolonged travel time. On the other hand, if the attach area is higher than the pick up area, the propensity of the transfer arm to prang into the heater block cover will increase drastically.
As we all know, there are copious die sizes. Hence, different collets with the suitable size corresponding to the type of die handled are required. With that information in mind, I helped Miss Manggala to complete a subservient task, which was to check for any die sizes of package SOT363/SC88, from the intranet, which were not listed in a table of die dimensions that NXP Semiconductor is currently having. She will then need to make the purchase of those collets.
After completing the task, I proceeded to gain a deeper understanding of wire bonding process. First off, I stumbled upon what PHICOM really means. It is actually the acronym for Philips Computer. PHICOM machine is meant for wire bonding process. Generally, six steps are involved. I will provide the steps with the aid of the following pictures.
1) The capillary is moving from the spark to ball bond position. When the Free Air Ball (FAB) touches the die, which is also known as touchdown, the ball bonding process starts. Note that FAB is bonded on the die at elevated temperature, pressure and ultrasonic energy.
2) After bonding the ball, capillary makes the wire loop.
3) The capillary lands on the lead and wedge bonding process starts.
4) The capillary moves up. Next, wire-clamp is closed. The capillary moves further up to break the wire and thus from the tail (wedge).
5) As the wire reaches spark height, a tail is hanging under the capillary.
6) A spark forms a ball at the end of the wire. The wire-clamp opens and the air jet pulls the ball inside the capillary.
If you were heedful when reading the steps aforementioned, you would wonder, what is the purpose of ultrasonic energy? Actually, it serves as an avenue to wipe away oxides or undesirable contaminations on the contact area. Also, it helps to mature the bonding in combination with thermal energy. In other words, this insinuates that the ball bonding process can be carried out in a higher temperature. In addition, the presence of ultrasonic energy can soften the metal of Free Air Ball, thus rendering easier ball bonding process.
Apart from that, I had learnt that the difference between normal, reserve and trapezoid loop is the wire loop length. Besides, I got myself a fun fact too! Do you know that the melting point of gold is 1064°C? Oh! By the way, gold wire is the only material used for wire bonding.
I realized that the insipidity of this industrial training had returned when I was again ordered to update bonding diagrams. Now for SC88 package. Again, due to my fast execution, I was able to finish it by today.
30 April 2010
Mundane, sedentary nature of work is fast becoming an idiosyncratic aspect of my industrial training. Sporadic clandestine self permitted time off from facing the computer proved to be the only humdinger of my industrial training life. I started off the day doing again petty task, which is to tabulate the values I obtained from previous measurements into Microsoft Excel. As an overview, I tabulated ball diameter, ball height, wire pull, break point, ball shear as well as free air ball.
Next, try guessing what I was assigned to do. It was none other than the exasperating bonding diagrams!! I was given new package to update, namely SC70 and SC75. At the end of the day, I was able to complete them. I even had the luxury of calculating the bonding diagrams that I had done so far.
Wednesday, April 28, 2010
26-28 April 2010
26 April 2010
I finished re-updating the bonding diagrams of SOT753P package. So, till today, I had re-updated SOT353P, SOT363P and SOT753P package, with one package having approximately 110 devices. An inexorable sense of achievement gushed up upon me. Next, I was given a new package, SC74 to update the bonding diagrams. I duly obliged and finished the task within considerably short period of time. I finished off the day with the ever-intriguing ball shear measurement. This time around, I had to perform it alone without the supervision of seniors or operators. It was challenging and fun. I put my flippancy aside and began to acquaint myself with the machine. Owing to my inexperience and slipshod nature, some dies were wrecked; some ball bonds were flattened and so forth. It would be preposterous to suggest that I was not traumatized. Fortuitously, the “debacle” that I had instigated was indiscernible.
27 April 2010
I was given the fifth package to update the bonding diagrams, SOT457P and was able to finish it within today. Subsequently, I was brought to the line where I gained knowledge on several things. Firstly, cross sectional view tests are performed on molded products or finished products to check for any copper interconnect and improper die attachment. Probable causes of imperfect die attachment are excessive bond force and exceedingly high temperature. One example of flawed die attachment is tilted die. Tilted die, along with lifted die or similar defects will culminate in the product be labeled as Rth units. These units will have high resistance, due to the voids between the die and the lead frame. On the other hand, copper interconnect can be reckoned as imperfect diffusion taken place between the die back metal and the lead frame substrate. Lead frames are made from copper. Under copper interconnect conditions; the back metal has copper particles diffused into it.
Next, Miss Manggala provided me with some SEM images which were done using devices far more superior than those powerful microscopes that I had used before. The SEM images were extremely clear. Besides that, high magnification can be attained.
I learned a new term today, by the name, collet. Collet is the protruding edge of a die bonding machine used to pick up individual die from a wafer. If the collet is filthy, the dies may be picked up in undesirable orientation or position, which may result in tilted dies. Hence, it must be cleaned regularly using propanol.
There are myriads of aspects that can engender defects, such as imperfections to the die, chipped die, cracked die; imperfections to the wire, offbond, exposed lead and so forth. Therefore, we need delayering analysis, where one can inspect and determine the root cause of failed products.
Lastly for today, some dies are large, which may pose inextricable difficulties in adhering them well to their respective bondpads. Hence, WBC or Wafer Back Coat is used to assuage this predicament. This is one type of glue bonding.
28 April 2010
I started off the day performing and finishing both ball shear measurement and wafer inspection. As I had mentioned in previous blog entries, a wafer may consists of few hundred thousands of dies. There is a possibility some dies are chipped, cracked or physically imperfect. That is the purpose behind me performing the wafer inspection.
Next, I was asked by Miss Manggala to have a roam around the assembly line. A casual stroll in the assembly line provided me with opportunities to gain some valuable knowledge. First off is the sporadic green light shining on lead frames in ADAT die bonding machines. By the way, ADAT is the acronym for Advanced Die Attach Technology. The occasional green light is meant as a visual or lighting aid for PRS, which is Pattern Recognition System. This system is designated for the ADAT machine to recognize good as well as bad dies. The picture below illustrates the PRS concept.
I was also introduced to Pepperpot by Mr Leong, an industrious engineer working along the line. Pepperpot is actually the vacuum head of the ADAT machine, which is used to ensure that the mylar does not stick along with the die when the die is picked up by the collet. It does so by adhering the mylar to the vacuum head.
Besides that, I gained a deeper understanding why BSOB is momentous in double dies wire bonding. Again, BSOB means Ball Stitched On Ball. Usually, in wire bonding, a ball is bonded on the die (ball bonding), while a wedge is bonded on the leadframe (wedge bonding). When double dies are involved, BSOB is implemented. One of the dies will be bonded first with a ball, then with a wedge on top of that ball. This combination is called a bump and acts as a cushion that protects the die from the high force entailed during wedge bonding.
Subsequently, Mr Leong explained the purpose of having two rectangular boxes just after several ADAT bonding machine. These boxes serve as ovens to dry or solidify the glue used for die bonding. Before I go into details of the boxes, let me deviate to the available types of die bonding. Die bonding process can be categorized into eutectic process, epoxy process and soft solder process. In NXP Semiconductor, soft solder process is not used. The discrepancies between eutectic and epoxy process are that eutectic process entails melting and solidifying two components (alloy), forming tri-alloy, such as AuSiAg (Gold Silicon and Silver) and AuGeAg (Gold, Germanium and Silver).
Epoxy process or glue bonding, however, involves the use of adhesive resin. Furthermore, epoxy or glue process is relatively cheaper than eutectic process. In addition, Epoxy process is conducted at a comparatively lower temperature than eutectic process. Now, back to the ovens; So, with the die bonding information in mind, it is equitable that only epoxy process will be needing ovens. If the glue is not dried, the die may budge or move around.
A pictorial representation of the types of die bonding process:
Besides the boxes, the discerning eyes of me caught sight of the changing colours of lead frames in different part of the process. This is due to the oxidation process. Apart from that, the relatively slow speed of some ADAT machines caught my attention too. After some cogent explanation from Mr Leong, I was able to know that these machines are producing power products which use dies with larger size. The low speed is indispensable to ensure that sufficient amount of time is present for the die attachment to take place properly.
I had also gained further understanding of die bonding process. There are 5 prominent issues with die bonding:
1) Must not transmit destructive stress to fragile chip
2) Must make intimate contact between chip and substrate with no voids and adhere well to both
3) Able to withstand high temperature
4) Must have good thermal conductivity: to remove heat generated within chip
5) Must be a good conductor or insulator, depending on application
I was also told by Miss Manggala that there are 3 parameters that are significant in die bonding process, which are temperature, bond force and process delay. Generally, die bonding process can be subdivided into 4 modules, die select, die pick up, die transfer and die attach.
I finished re-updating the bonding diagrams of SOT753P package. So, till today, I had re-updated SOT353P, SOT363P and SOT753P package, with one package having approximately 110 devices. An inexorable sense of achievement gushed up upon me. Next, I was given a new package, SC74 to update the bonding diagrams. I duly obliged and finished the task within considerably short period of time. I finished off the day with the ever-intriguing ball shear measurement. This time around, I had to perform it alone without the supervision of seniors or operators. It was challenging and fun. I put my flippancy aside and began to acquaint myself with the machine. Owing to my inexperience and slipshod nature, some dies were wrecked; some ball bonds were flattened and so forth. It would be preposterous to suggest that I was not traumatized. Fortuitously, the “debacle” that I had instigated was indiscernible.
27 April 2010
I was given the fifth package to update the bonding diagrams, SOT457P and was able to finish it within today. Subsequently, I was brought to the line where I gained knowledge on several things. Firstly, cross sectional view tests are performed on molded products or finished products to check for any copper interconnect and improper die attachment. Probable causes of imperfect die attachment are excessive bond force and exceedingly high temperature. One example of flawed die attachment is tilted die. Tilted die, along with lifted die or similar defects will culminate in the product be labeled as Rth units. These units will have high resistance, due to the voids between the die and the lead frame. On the other hand, copper interconnect can be reckoned as imperfect diffusion taken place between the die back metal and the lead frame substrate. Lead frames are made from copper. Under copper interconnect conditions; the back metal has copper particles diffused into it.
Next, Miss Manggala provided me with some SEM images which were done using devices far more superior than those powerful microscopes that I had used before. The SEM images were extremely clear. Besides that, high magnification can be attained.
I learned a new term today, by the name, collet. Collet is the protruding edge of a die bonding machine used to pick up individual die from a wafer. If the collet is filthy, the dies may be picked up in undesirable orientation or position, which may result in tilted dies. Hence, it must be cleaned regularly using propanol.
There are myriads of aspects that can engender defects, such as imperfections to the die, chipped die, cracked die; imperfections to the wire, offbond, exposed lead and so forth. Therefore, we need delayering analysis, where one can inspect and determine the root cause of failed products.
Lastly for today, some dies are large, which may pose inextricable difficulties in adhering them well to their respective bondpads. Hence, WBC or Wafer Back Coat is used to assuage this predicament. This is one type of glue bonding.
28 April 2010
I started off the day performing and finishing both ball shear measurement and wafer inspection. As I had mentioned in previous blog entries, a wafer may consists of few hundred thousands of dies. There is a possibility some dies are chipped, cracked or physically imperfect. That is the purpose behind me performing the wafer inspection.
Next, I was asked by Miss Manggala to have a roam around the assembly line. A casual stroll in the assembly line provided me with opportunities to gain some valuable knowledge. First off is the sporadic green light shining on lead frames in ADAT die bonding machines. By the way, ADAT is the acronym for Advanced Die Attach Technology. The occasional green light is meant as a visual or lighting aid for PRS, which is Pattern Recognition System. This system is designated for the ADAT machine to recognize good as well as bad dies. The picture below illustrates the PRS concept.
I was also introduced to Pepperpot by Mr Leong, an industrious engineer working along the line. Pepperpot is actually the vacuum head of the ADAT machine, which is used to ensure that the mylar does not stick along with the die when the die is picked up by the collet. It does so by adhering the mylar to the vacuum head.
Besides that, I gained a deeper understanding why BSOB is momentous in double dies wire bonding. Again, BSOB means Ball Stitched On Ball. Usually, in wire bonding, a ball is bonded on the die (ball bonding), while a wedge is bonded on the leadframe (wedge bonding). When double dies are involved, BSOB is implemented. One of the dies will be bonded first with a ball, then with a wedge on top of that ball. This combination is called a bump and acts as a cushion that protects the die from the high force entailed during wedge bonding.
Subsequently, Mr Leong explained the purpose of having two rectangular boxes just after several ADAT bonding machine. These boxes serve as ovens to dry or solidify the glue used for die bonding. Before I go into details of the boxes, let me deviate to the available types of die bonding. Die bonding process can be categorized into eutectic process, epoxy process and soft solder process. In NXP Semiconductor, soft solder process is not used. The discrepancies between eutectic and epoxy process are that eutectic process entails melting and solidifying two components (alloy), forming tri-alloy, such as AuSiAg (Gold Silicon and Silver) and AuGeAg (Gold, Germanium and Silver).
Epoxy process or glue bonding, however, involves the use of adhesive resin. Furthermore, epoxy or glue process is relatively cheaper than eutectic process. In addition, Epoxy process is conducted at a comparatively lower temperature than eutectic process. Now, back to the ovens; So, with the die bonding information in mind, it is equitable that only epoxy process will be needing ovens. If the glue is not dried, the die may budge or move around.
A pictorial representation of the types of die bonding process:
Besides the boxes, the discerning eyes of me caught sight of the changing colours of lead frames in different part of the process. This is due to the oxidation process. Apart from that, the relatively slow speed of some ADAT machines caught my attention too. After some cogent explanation from Mr Leong, I was able to know that these machines are producing power products which use dies with larger size. The low speed is indispensable to ensure that sufficient amount of time is present for the die attachment to take place properly.
I had also gained further understanding of die bonding process. There are 5 prominent issues with die bonding:
1) Must not transmit destructive stress to fragile chip
2) Must make intimate contact between chip and substrate with no voids and adhere well to both
3) Able to withstand high temperature
4) Must have good thermal conductivity: to remove heat generated within chip
5) Must be a good conductor or insulator, depending on application
I was also told by Miss Manggala that there are 3 parameters that are significant in die bonding process, which are temperature, bond force and process delay. Generally, die bonding process can be subdivided into 4 modules, die select, die pick up, die transfer and die attach.
Thursday, April 22, 2010
20-23 April 2010
20 April 2010
I finished adding colours to the wires for SOT353 bonding diagrams. Basically, I need to choose from three colours to be used, namely black, blue and red. The criteria that I need to consider in selecting the correct colour is already there in the bonding diagram. If normal looping is written, the wires should be of black colour, blue colour for reverse loop and red colour for trapezoid loop.
Besides adding colours, I was told to check on erroneous lead frame diagrams implemented by previous document control personnel. The scope of search was limited to SOT353 and SOT753 package. I was able to find and remedy 9 incorrect SOT353 bonding diagrams as well as 7 incorrect SOT753 bonding diagrams.
Lastly, I was asked to obtain the amount of wires used for each NXP Semiconductor product by referring to the intranet. For your information, there are 1956 products.
21 April 2010
I continued the work of re-updating bonding diagrams after finishing SOT353 package. The current package that I am working on is SOT363. At the mean time, I am also implicating myself in ball height and diameter measurement as well as acquiring number of wires used in bonding diagrams via intranet. Besides all those easy but repetition-oriented tasks, I learned the term BSOB, which means Ball Stitched On Ball. The following picture provides the illustration.
My prosaic industrial training experience took an unexpected and invigorating twist today. I was asked to teach a lab operator on how to acquire ball bond and die images using microscopes. I guess all those repetition of work had made me a veritable measurement, data updating and acquisition specialist. Although tutoring was a brisk experience, I am yearning for engineering tasks which I can apply some engineering knowledge to challenge my brain.
22 April 2010
I had finished recording the wire amount for 1956 products in NXP Semiconductor. I continued my measurement of ball height and diameter. Just to refresh your memory. I have 720 measurements to be made. Although my work is saturated with utmost boredom, I kept indolence at bay and proceeded my work with swift execution, hoping that I can quickly escape this welter of simple jobs and probably get some challenging tasks.
Hours after lunch, Miss Manggala brought me and demonstrated wafer inspection under microscope. I was taught edge dies are usually chipped or flawed. This is acceptable. However, other than the edge dies, any chipped or flawed dies will be deemed as unacceptable. I will provide a hand drawn illustration of the wafer as well as what it looks like under microscope. Again, I could not take pictures of the wafer as Miss Manggala said it would probably infringe company rights.
Apart from that, I also inspected decapped products. As i had mentioned before, the finished dies will be molded using resin compound to provide some sort of protection or cover. By decapping, we can inspect and check for deficiencies in the dies that lie within the mold. I managed to discover mixed devices where wrong die type is used for that particular product.
I finished off the day performing free air ball measurement. Similar to ball height and ball diameter measurement, free air ball refers to the ball formed by the PHICOM wire bonding machine just before it is bonded on the die.
23 April 2010
I finished free air ball, ball height and diameter measurement as well as the tabulation of those data in Microsoft Excel. I had also finished re-updating SOT363 bonding diagrams and duly continued with SOT753 package. Besides all those antagonizing works, I managed to learn that there are generally two types of lead frames, namely bi lead frame and matrix lead frame. By referring to the picture shown, the upper lead frame is of bi type while the bottom one represents matrix lead frame.
Furthermore, I had also gone through verification flow chart for chipped package as well as scratched package. A picture speaks a thousand words, here goes:
I finished adding colours to the wires for SOT353 bonding diagrams. Basically, I need to choose from three colours to be used, namely black, blue and red. The criteria that I need to consider in selecting the correct colour is already there in the bonding diagram. If normal looping is written, the wires should be of black colour, blue colour for reverse loop and red colour for trapezoid loop.
Besides adding colours, I was told to check on erroneous lead frame diagrams implemented by previous document control personnel. The scope of search was limited to SOT353 and SOT753 package. I was able to find and remedy 9 incorrect SOT353 bonding diagrams as well as 7 incorrect SOT753 bonding diagrams.
Lastly, I was asked to obtain the amount of wires used for each NXP Semiconductor product by referring to the intranet. For your information, there are 1956 products.
21 April 2010
I continued the work of re-updating bonding diagrams after finishing SOT353 package. The current package that I am working on is SOT363. At the mean time, I am also implicating myself in ball height and diameter measurement as well as acquiring number of wires used in bonding diagrams via intranet. Besides all those easy but repetition-oriented tasks, I learned the term BSOB, which means Ball Stitched On Ball. The following picture provides the illustration.
My prosaic industrial training experience took an unexpected and invigorating twist today. I was asked to teach a lab operator on how to acquire ball bond and die images using microscopes. I guess all those repetition of work had made me a veritable measurement, data updating and acquisition specialist. Although tutoring was a brisk experience, I am yearning for engineering tasks which I can apply some engineering knowledge to challenge my brain.
22 April 2010
I had finished recording the wire amount for 1956 products in NXP Semiconductor. I continued my measurement of ball height and diameter. Just to refresh your memory. I have 720 measurements to be made. Although my work is saturated with utmost boredom, I kept indolence at bay and proceeded my work with swift execution, hoping that I can quickly escape this welter of simple jobs and probably get some challenging tasks.
Hours after lunch, Miss Manggala brought me and demonstrated wafer inspection under microscope. I was taught edge dies are usually chipped or flawed. This is acceptable. However, other than the edge dies, any chipped or flawed dies will be deemed as unacceptable. I will provide a hand drawn illustration of the wafer as well as what it looks like under microscope. Again, I could not take pictures of the wafer as Miss Manggala said it would probably infringe company rights.
Apart from that, I also inspected decapped products. As i had mentioned before, the finished dies will be molded using resin compound to provide some sort of protection or cover. By decapping, we can inspect and check for deficiencies in the dies that lie within the mold. I managed to discover mixed devices where wrong die type is used for that particular product.
I finished off the day performing free air ball measurement. Similar to ball height and ball diameter measurement, free air ball refers to the ball formed by the PHICOM wire bonding machine just before it is bonded on the die.
23 April 2010
I finished free air ball, ball height and diameter measurement as well as the tabulation of those data in Microsoft Excel. I had also finished re-updating SOT363 bonding diagrams and duly continued with SOT753 package. Besides all those antagonizing works, I managed to learn that there are generally two types of lead frames, namely bi lead frame and matrix lead frame. By referring to the picture shown, the upper lead frame is of bi type while the bottom one represents matrix lead frame.
Furthermore, I had also gone through verification flow chart for chipped package as well as scratched package. A picture speaks a thousand words, here goes:
Wednesday, April 21, 2010
19 April 2010
I completed the acquisition of ball images. Swiftly after that, I finished updating the additional ECO assigned. To be frank, the work that I have been doing does not seem to be of any significance in engineering point of view. I felt like and still feel like I am merely an office boy. As a matter of fact, one of the document control personnel told me that I did a colossal favour in helping them clearing their avalanche of unfinished tasks, like updating bonding diagrams. Not to mention helping the engineering department to run all the measurements, input acquisitions and so forth. These works, to be blunt, irk and antagonize me. I feel anguished. I feel like my engineering knowledge was put to no use at all. Those are the jobs that an ordinary person can accomplish. I feel like this industrial training is a huge waste of time. I could utilize this time to embark on something more beneficial. To add insult to injury, my eyes have been in excruciating pain as all I was doing was just staring at the merciless computer which just radiates incessant stream of baneful rays straight at my face. Worse still, no one seems to care even thought I had requested for a monitor ray filter. I was just rebuffed. I feel like I am a cheap labour. A very cheap labour. I had completed so much task in such a short time, and I only get myself a scant 500 per month. No subsidies, no leaves.....This is an unequivocal living purgatory.
I am not trying to be pedantic, but my internship just keeps getting obnoxious. I was required to add colour to wires in the bonding diagrams that I had just updated. It sound simplistic, but in fact, it entails a tremendously tedious and troublesome process using Microsoft Visio, Microsoft Powerpoint and Acrobat Reader. In other words, I need to rework the 300 odd bonding diagrams that I had completed. Mind you, it takes 6-7 minutes just to get one of these done. The reason behind this addition is to enhance operators' understanding of the bonding diagrams. Come on, there are already ample information on the bonding diagram. Why put something gratuitous? At least notify me when I started out updating the bonding diagrams early on. Again, are these what engineers should do?
I am not trying to be pedantic, but my internship just keeps getting obnoxious. I was required to add colour to wires in the bonding diagrams that I had just updated. It sound simplistic, but in fact, it entails a tremendously tedious and troublesome process using Microsoft Visio, Microsoft Powerpoint and Acrobat Reader. In other words, I need to rework the 300 odd bonding diagrams that I had completed. Mind you, it takes 6-7 minutes just to get one of these done. The reason behind this addition is to enhance operators' understanding of the bonding diagrams. Come on, there are already ample information on the bonding diagram. Why put something gratuitous? At least notify me when I started out updating the bonding diagrams early on. Again, are these what engineers should do?
Friday, April 16, 2010
14-16 April 2010
14 April 2010
By today, I can reckon myself as being highly efficient and dexterous in handling the microscope meant for ball diameter as well as height measurement. I finished off the measurement of the remaining samples and proceeded with the tabulation of the data in Microsoft Word and Excel. Also, I was required to calculate the three average values for each sample. As I had mentioned before, each sample will be evaluated a total of 15 times for ball height as well as ball diameter. These 15 evaluations were categorized into 3 groups for each sample.
Apart from that, I was taught of the reason behind using gold wires for wire bonding processes. According to Miss Manggal as well as the line operators that I had encountered. Gold wires offer stupendous conductivity and impervious to oxidation. These advantages overshadow gold wire exorbitant pricing. On the other hand, copper wire may be relatively cheap, but it is susceptible to oxidation. Hence, using copper in wire bonds will instigate rusting of wire bonds, thereby undermining the bond desired properties.
15 April 2010
I was introduced to ECO, which is the acronym for Engineering Change Order. I was taught on how to access NXP Semiconductor intranet where only certified employees can gain access to its cross nation database. Upon opening up the file containing the sale items, I was left in absolute awe as NXP Semiconductor deals with a plethora of product. Then, I was taught on how to update the ECO of some products here in NXP Assembly Plant Malaysia (APM).
Owing to my fantastic hand-eye coordination and diligence, I was able to complete updating ECO in the wink of an eye. Of course, I do not mean it literally. Next, to kill of time before Miss Manggala assign me tasks, I read through the verification flow for chipped package and scratched package. Then, Miss Dahlia asked me to stamp and sort those printed updated bonding diagrams that I had done.
After that, I was brought into the assembly line where I got to witness and perform ball shear measurement. Previously, I had dealt with the measurement of ball height and diameter. Now, the gist of this measurement is to test for the ball type wire bonding on each individual die. This task was really a much sought after break away from all the needs of facing computer all day long. In fact, it was extremely mind-boggling and exciting! My fun buds definitely got aroused. Not to mention hilarious as Miss Manggala and Miss Sally were providing animated and amusing tutorials.
This task really entails splendid hand-eye coordination as while one is looking at the die through microscope, one needs to utilize the joystick-like controls to position a special protruding section of the device just beside the ball bond on the die. Next, with a press of the ball shear button, a force will be applied as to displace the ball. Then, the required force to attain that will be displayed and to be recorded. Owing to my inexperience, my movements were completely sluggish and tentative. Worse-still, I "managed" to obliterate or flatten a ball because of incorrect positioning of the ball shear device which incur nothing but laughter from Miss Manggala and Miss Sally. After completing the measurement, I returned and recorded the values in Microsoft Excel under the same file as the one I recorded the ball diameter and height values. Average values were calculated too.
Ya. Another test that eluded me is wire pull. Probably due to its complexity, I was not taught on how to perform it. This test is to determine the strength of the wire bonding.
16 April 2010
I finished marking and sorting SOT353, SOT 363 and SOT 753 printed bonding diagrams. This consists of around 500 sheets of paper encompassing previous flawed bonding diagrams. Upon completion of the task, I was summoned to the New Product Introduction Lab where I was granted my wish of viewing my fingers under microscope. It was irrefutably an awesome experience. I got to see the sweat droplets, finger prints, hair and so forth.
Well, I spent the rest of the day acquiring ball images using microscope. If you had notice, I used the term microscope for numerous times. Actually, they are not the same device. I regard them generally as microscopes as I have no idea of what their specific names are. Again, coming back to the 16 samples that I had worked on for ball diameter, height and ball shear, I need to acquire 3 images for each sample. I will provide one of the images that I had captured.
By today, I can reckon myself as being highly efficient and dexterous in handling the microscope meant for ball diameter as well as height measurement. I finished off the measurement of the remaining samples and proceeded with the tabulation of the data in Microsoft Word and Excel. Also, I was required to calculate the three average values for each sample. As I had mentioned before, each sample will be evaluated a total of 15 times for ball height as well as ball diameter. These 15 evaluations were categorized into 3 groups for each sample.
Apart from that, I was taught of the reason behind using gold wires for wire bonding processes. According to Miss Manggal as well as the line operators that I had encountered. Gold wires offer stupendous conductivity and impervious to oxidation. These advantages overshadow gold wire exorbitant pricing. On the other hand, copper wire may be relatively cheap, but it is susceptible to oxidation. Hence, using copper in wire bonds will instigate rusting of wire bonds, thereby undermining the bond desired properties.
15 April 2010
I was introduced to ECO, which is the acronym for Engineering Change Order. I was taught on how to access NXP Semiconductor intranet where only certified employees can gain access to its cross nation database. Upon opening up the file containing the sale items, I was left in absolute awe as NXP Semiconductor deals with a plethora of product. Then, I was taught on how to update the ECO of some products here in NXP Assembly Plant Malaysia (APM).
Owing to my fantastic hand-eye coordination and diligence, I was able to complete updating ECO in the wink of an eye. Of course, I do not mean it literally. Next, to kill of time before Miss Manggala assign me tasks, I read through the verification flow for chipped package and scratched package. Then, Miss Dahlia asked me to stamp and sort those printed updated bonding diagrams that I had done.
After that, I was brought into the assembly line where I got to witness and perform ball shear measurement. Previously, I had dealt with the measurement of ball height and diameter. Now, the gist of this measurement is to test for the ball type wire bonding on each individual die. This task was really a much sought after break away from all the needs of facing computer all day long. In fact, it was extremely mind-boggling and exciting! My fun buds definitely got aroused. Not to mention hilarious as Miss Manggala and Miss Sally were providing animated and amusing tutorials.
This task really entails splendid hand-eye coordination as while one is looking at the die through microscope, one needs to utilize the joystick-like controls to position a special protruding section of the device just beside the ball bond on the die. Next, with a press of the ball shear button, a force will be applied as to displace the ball. Then, the required force to attain that will be displayed and to be recorded. Owing to my inexperience, my movements were completely sluggish and tentative. Worse-still, I "managed" to obliterate or flatten a ball because of incorrect positioning of the ball shear device which incur nothing but laughter from Miss Manggala and Miss Sally. After completing the measurement, I returned and recorded the values in Microsoft Excel under the same file as the one I recorded the ball diameter and height values. Average values were calculated too.
Ya. Another test that eluded me is wire pull. Probably due to its complexity, I was not taught on how to perform it. This test is to determine the strength of the wire bonding.
16 April 2010
I finished marking and sorting SOT353, SOT 363 and SOT 753 printed bonding diagrams. This consists of around 500 sheets of paper encompassing previous flawed bonding diagrams. Upon completion of the task, I was summoned to the New Product Introduction Lab where I was granted my wish of viewing my fingers under microscope. It was irrefutably an awesome experience. I got to see the sweat droplets, finger prints, hair and so forth.
Well, I spent the rest of the day acquiring ball images using microscope. If you had notice, I used the term microscope for numerous times. Actually, they are not the same device. I regard them generally as microscopes as I have no idea of what their specific names are. Again, coming back to the 16 samples that I had worked on for ball diameter, height and ball shear, I need to acquire 3 images for each sample. I will provide one of the images that I had captured.
Wednesday, April 14, 2010
12-13 April 2010
This is the start of a brand new week. I started off with yet another educational visit around the assembly line, led by Miss Manggala. This time around, I was brought to a few compartments designated for research and experiment purposes. I was introduced to several experienced personnel, who greeted me with some typical questions like how long will I be having my internship, where do I live, where am I studying and so forth. All of them were undeniably jovial and gregarious as uproarious mirth filled the air. However, after I left those rooms, I could sense their taciturnity as they cut a forlorn and morose figure beneath those cheerful semblances as they returned to their respective operating position. Maybe this is what we known as Monday Blues.
Later on, Miss Manggala told me to roam around, be acquainted with the environment, and to observe the actions carried out by the assembly line staffs, be it front end, mid end or back end staffs. First off, I stumbled upon the terms batch number, index number and shift number. Basically, they refer to the output quantity. However, there are few distinctions. Batch number refers to the current die type output quantity. Index number refers to the number of dies produced, regardless of the die type, as the machine senses the number of index hole on the lead frame instead of the individual dies. Customarily, batch number is the same as index number. Next is shift number which refers to the output quantity that the current shift has produced. For your information, there are three working shifts. Apart from that, I also came across terms such as processed die, remaining die and units per minute. As I had mentioned in previous posts, each wafer may contain hundred thousand of dies. Processed die connotes the idea of how many dies that had been extracted by the die bond machine for the bonding processes; and as the name itself implies, remaining die tells us the number of available die on the wafer. Note that the processed die value is inadvertently greater than that of batch number as some dies may be substandard and duly discarded. Moving on, units per minute suggest the speed at which the machine operates. For typical die bond processes using ADAT 2 Machine, the speed is approximately 302 units per minute!
Besides that, I had also observed how the technicians carry out wafer substitution to replace exhausted wafer. Normally after replacing the wafer, they will use Propane to clean up the tip of the machine which is used to extract dies from the wafer. Moreover, these technicians will rely on the alarm triggered or visual inspection of operation light on each machine to realize erroneous processes had occurred. As usual, green light brings about the idea of normal, error-free production process, whereas red light impinges on the notion of error occurrence. Yellow light, on the other hand, indicates that the machine is in idle mode. Furthermore, I had also witnessed how welding processes were done to combines separate lead frames. Lead frames are stored in circular reels. These reels of lead frames serve as the input to almost all machines. As these reels run out of lead frames, production process at that machine will be stopped, pristine reel of lead frames will be attached to the machine, replacing the exhausted reel. The lead frames of the previous reel will now be welded together with that of the new reel, using a welding machine.
As I saunter more, I discovered more. I perceived how the indefatigable operators conduct wafer mounting processes using an expansion device. I also got to see how the dies, wire bonds look like under microscopes. The operators were obliging and helpful as they effortlessly explained coherently what variables that could culminate in imperfect dies or bonds. For instance, excessive bond force exerted by the PHICOM wire bonding machine will engender flawed bond shape.
After those horizon broadening encounters, Miss Manggala came back for me and taught me how to measure wire bond height as well as bond diameter. The microscope meant for this is not just ordinary microscope. It is a highly sophisticated microscope that can enable us to see minute object measuring few micrometers clearly. I spent few hours measuring 16 samples of lead frames. Each sample will have 15 entries of bond height as well as 15 entries of bond diameter. Indolence and nonchalance started to kick in due to the monotonicity but my forbearance prevailed. In fact, I got a little bit exhilarated as I was able to see how the dies, the bonds, the lead frames look like under the microscope.
I could not finish the measurement today as there were a lot of operators who had queued up the utilize that machine. I felt like I was an eminent singer who has long queue of ardent fans jostling for my autograph. Finally, they asked me if I could return tomorrow for the measurement and I duly obliged. I returned to my desk where I was given the third package, SOT363 to update the bonding diagrams.
By the end of 13 April 2010, I completed updating the SOT673 package bonding diagrams, which takes the amount of bonding diagrams that I had encountered so far, to approximately 300. However, the same cannot be said of the measurement of bond height and bond diameter as the device was so in demand I could only use it for short periods of time.
Later on, Miss Manggala told me to roam around, be acquainted with the environment, and to observe the actions carried out by the assembly line staffs, be it front end, mid end or back end staffs. First off, I stumbled upon the terms batch number, index number and shift number. Basically, they refer to the output quantity. However, there are few distinctions. Batch number refers to the current die type output quantity. Index number refers to the number of dies produced, regardless of the die type, as the machine senses the number of index hole on the lead frame instead of the individual dies. Customarily, batch number is the same as index number. Next is shift number which refers to the output quantity that the current shift has produced. For your information, there are three working shifts. Apart from that, I also came across terms such as processed die, remaining die and units per minute. As I had mentioned in previous posts, each wafer may contain hundred thousand of dies. Processed die connotes the idea of how many dies that had been extracted by the die bond machine for the bonding processes; and as the name itself implies, remaining die tells us the number of available die on the wafer. Note that the processed die value is inadvertently greater than that of batch number as some dies may be substandard and duly discarded. Moving on, units per minute suggest the speed at which the machine operates. For typical die bond processes using ADAT 2 Machine, the speed is approximately 302 units per minute!
Besides that, I had also observed how the technicians carry out wafer substitution to replace exhausted wafer. Normally after replacing the wafer, they will use Propane to clean up the tip of the machine which is used to extract dies from the wafer. Moreover, these technicians will rely on the alarm triggered or visual inspection of operation light on each machine to realize erroneous processes had occurred. As usual, green light brings about the idea of normal, error-free production process, whereas red light impinges on the notion of error occurrence. Yellow light, on the other hand, indicates that the machine is in idle mode. Furthermore, I had also witnessed how welding processes were done to combines separate lead frames. Lead frames are stored in circular reels. These reels of lead frames serve as the input to almost all machines. As these reels run out of lead frames, production process at that machine will be stopped, pristine reel of lead frames will be attached to the machine, replacing the exhausted reel. The lead frames of the previous reel will now be welded together with that of the new reel, using a welding machine.
As I saunter more, I discovered more. I perceived how the indefatigable operators conduct wafer mounting processes using an expansion device. I also got to see how the dies, wire bonds look like under microscopes. The operators were obliging and helpful as they effortlessly explained coherently what variables that could culminate in imperfect dies or bonds. For instance, excessive bond force exerted by the PHICOM wire bonding machine will engender flawed bond shape.
After those horizon broadening encounters, Miss Manggala came back for me and taught me how to measure wire bond height as well as bond diameter. The microscope meant for this is not just ordinary microscope. It is a highly sophisticated microscope that can enable us to see minute object measuring few micrometers clearly. I spent few hours measuring 16 samples of lead frames. Each sample will have 15 entries of bond height as well as 15 entries of bond diameter. Indolence and nonchalance started to kick in due to the monotonicity but my forbearance prevailed. In fact, I got a little bit exhilarated as I was able to see how the dies, the bonds, the lead frames look like under the microscope.
I could not finish the measurement today as there were a lot of operators who had queued up the utilize that machine. I felt like I was an eminent singer who has long queue of ardent fans jostling for my autograph. Finally, they asked me if I could return tomorrow for the measurement and I duly obliged. I returned to my desk where I was given the third package, SOT363 to update the bonding diagrams.
By the end of 13 April 2010, I completed updating the SOT673 package bonding diagrams, which takes the amount of bonding diagrams that I had encountered so far, to approximately 300. However, the same cannot be said of the measurement of bond height and bond diameter as the device was so in demand I could only use it for short periods of time.
9 April 2010
This entry is going to be relatively compendious. I continued what I had left off yesterday, which was the updating of bonding diagrams. I felt like I was a clerk instead of an engineer. I felt like I was a machine instead of a human. I felt like I was languishing in a sea of PDF files, Powerpoint slides...
There a always two sides to a coin. The only positive impact I had felt was that my speed in dealing with Powerpoint slides and PDF files had exponentially increased. I could literally shut my eyes and performed all those tasks impeccably.
By the end of the day, I had successfully completed updating the bonding diagrams of SOT753 and SOT 353 packages, as well as their respective flat location, if any. This would amount to a total of approximately 200 bonding diagrams. Fuiyoh! I am really fast! Oh ya! Flat location means the position of the wafer on the ADAT die bonding machine. There are a total of 8 possible orientations.
There a always two sides to a coin. The only positive impact I had felt was that my speed in dealing with Powerpoint slides and PDF files had exponentially increased. I could literally shut my eyes and performed all those tasks impeccably.
By the end of the day, I had successfully completed updating the bonding diagrams of SOT753 and SOT 353 packages, as well as their respective flat location, if any. This would amount to a total of approximately 200 bonding diagrams. Fuiyoh! I am really fast! Oh ya! Flat location means the position of the wafer on the ADAT die bonding machine. There are a total of 8 possible orientations.
Thursday, April 8, 2010
7-8 April 2010
It is unimpeachable that honesty is a virtue; and I intend to uphold that virtue in me. That is why I am going to say that the third and the forth day of my industrial training had been absolutely humdrum! Not to mention physically and mentally tormenting!!!
Upon arriving at the New Product Introduction Unit, I was introduced to my direct supervisor, Miss Manggala by my other supervisor, Mr. Melvin. She is an affable person with a warm smile emblazoning her face.
Then, both of them briefed me about documentation of bonding diagrams as well as the ratification of the flat location. What are those? Bonding diagrams are actually meant to show how the individual die or crystal containing certain circuitry is connected via tenuous gold wire to the bondpad on lead frames. There could be five connections or four connections, depending on the specifications. At the other end of the spectrum, flat location is the position of the wafer as it is used by the machine for die extraction. According to them, this is a momentous task as the assembly line hinges on the information that was about to be recorded. Any mistake that may be indiscernible may culminate in an execrable effect to the assembly line. Not to be rattled, I am a meticulous person. So I performed the task given after detailed explanation and demonstration from the Document Room's colleagues, Miss Dahlia and Miss Shree.
When I say it was mundane, I am not trying to pontificate. I really mean it as what i did for these two days was to face the computer whole day, copy, paste and edit approximately 200 diagrams. I would be preposterous if I had mentioned that I did not feel like I was a machine because what I did was just repetition of steps. My eyes were sore due to the prolonged exposure to the computer which is devoid of any means of harmful rays filtering. The only cheer that had brightened up my day was that I received compliments about the phenomenal rate of my work. To reward that, I was given more work of the exact type. To round it off, the work of these two days had been so monotonous that I had decided to create this new blog post which encapsulates these two days instead of individual post for each day.
Upon arriving at the New Product Introduction Unit, I was introduced to my direct supervisor, Miss Manggala by my other supervisor, Mr. Melvin. She is an affable person with a warm smile emblazoning her face.
Then, both of them briefed me about documentation of bonding diagrams as well as the ratification of the flat location. What are those? Bonding diagrams are actually meant to show how the individual die or crystal containing certain circuitry is connected via tenuous gold wire to the bondpad on lead frames. There could be five connections or four connections, depending on the specifications. At the other end of the spectrum, flat location is the position of the wafer as it is used by the machine for die extraction. According to them, this is a momentous task as the assembly line hinges on the information that was about to be recorded. Any mistake that may be indiscernible may culminate in an execrable effect to the assembly line. Not to be rattled, I am a meticulous person. So I performed the task given after detailed explanation and demonstration from the Document Room's colleagues, Miss Dahlia and Miss Shree.
When I say it was mundane, I am not trying to pontificate. I really mean it as what i did for these two days was to face the computer whole day, copy, paste and edit approximately 200 diagrams. I would be preposterous if I had mentioned that I did not feel like I was a machine because what I did was just repetition of steps. My eyes were sore due to the prolonged exposure to the computer which is devoid of any means of harmful rays filtering. The only cheer that had brightened up my day was that I received compliments about the phenomenal rate of my work. To reward that, I was given more work of the exact type. To round it off, the work of these two days had been so monotonous that I had decided to create this new blog post which encapsulates these two days instead of individual post for each day.
Tuesday, April 6, 2010
6 April 2010
Today, I decided to give my watch a day off. To me, this was an astute decision as I was oblivious to how slow the clock ticks. Time flew by today. Apart from that, I underwent several mind-challenging and intriguing activities.
To start off the day, I was instructed to complete a partial report containing just what I had learned during the first day. Some of the details that I had written are Assembly Plant Malaysia (APM) processes, introduction to semiconductor and organizational chart.
Upon completion of the first task, my supervisor, Mr. Melvin presented me with a mathematical problem involving wire bonding process. I was asked to find the percentage increase in gold wire cost if each individual die size is reduced by 4% from the two edges. Note that the die height is still the same and relevant parameter values were given according to their engineering specifications. So, by using the famous Pythagoras theorem, I was able to calculate the percentage increase in cost. Then, I was also required to devise a general equation for evaluating the percentage cost increase which consists of four variables, namely wire bonding horizontal length, percentage increase wire bonding horizontal length, die height and line height.
After the brief lunch break, I was introduced to DOE which stands for Design of Experiment as well as SPC (Statistical Process Control). In DOE, I had gained some basic knowledge on how to implement 2k full factorial design. It is unequivocal that for each process, there may be several input variables. Through DOE, and via Minitab software, I was able to produce information regarding the set of input variables as well as the output variables. There are four models of interest. Full model, final reduced model, graphical analysis and mathematical model. I was able to determine which input variables are statistically significant or otherwise. Those insignificant factors will be neglected for further analysis of the operation. At last, one would be able to determine the equation that governs the relationship between the sole output and a set of input variables. Besides that, the determination of process window, which can be esteemed as the range of allowable process variables, is of utmost importance. Process operation should be based on the values that are at the center of this particular process window.
In SPC, I was exposed to the use of process capability index, or capability index. This index relates the voice of the customer (specification limits) to the voice of the process. In other words, it is the ratio of the distance from the process center to the nearest specification limit divided by a measure of the process variability. This parameter is useful in determining whether the process if stable or otherwise as it inadvertently reduces the complex information about the process to a single number. If the result were to be greater than 1.67, then the process is reckoned to be stable. Customarily, we deal with two limits, one being the upper sided limit, while the other one, naturally, being the lower sided limit. So, this inextricably means that there will be two calculations of the capability index. The one which yields the lowest value is the one we are going to compare it with the standard value of 1.67. As an extra information, process capability index is influenced by the way the process data are collected, that is, the process view. Process view can be defined in terms of the time frame, sampling method (sampling frequency, size...) used to obtain process data.
To start off the day, I was instructed to complete a partial report containing just what I had learned during the first day. Some of the details that I had written are Assembly Plant Malaysia (APM) processes, introduction to semiconductor and organizational chart.
Upon completion of the first task, my supervisor, Mr. Melvin presented me with a mathematical problem involving wire bonding process. I was asked to find the percentage increase in gold wire cost if each individual die size is reduced by 4% from the two edges. Note that the die height is still the same and relevant parameter values were given according to their engineering specifications. So, by using the famous Pythagoras theorem, I was able to calculate the percentage increase in cost. Then, I was also required to devise a general equation for evaluating the percentage cost increase which consists of four variables, namely wire bonding horizontal length, percentage increase wire bonding horizontal length, die height and line height.
After the brief lunch break, I was introduced to DOE which stands for Design of Experiment as well as SPC (Statistical Process Control). In DOE, I had gained some basic knowledge on how to implement 2k full factorial design. It is unequivocal that for each process, there may be several input variables. Through DOE, and via Minitab software, I was able to produce information regarding the set of input variables as well as the output variables. There are four models of interest. Full model, final reduced model, graphical analysis and mathematical model. I was able to determine which input variables are statistically significant or otherwise. Those insignificant factors will be neglected for further analysis of the operation. At last, one would be able to determine the equation that governs the relationship between the sole output and a set of input variables. Besides that, the determination of process window, which can be esteemed as the range of allowable process variables, is of utmost importance. Process operation should be based on the values that are at the center of this particular process window.
In SPC, I was exposed to the use of process capability index, or capability index. This index relates the voice of the customer (specification limits) to the voice of the process. In other words, it is the ratio of the distance from the process center to the nearest specification limit divided by a measure of the process variability. This parameter is useful in determining whether the process if stable or otherwise as it inadvertently reduces the complex information about the process to a single number. If the result were to be greater than 1.67, then the process is reckoned to be stable. Customarily, we deal with two limits, one being the upper sided limit, while the other one, naturally, being the lower sided limit. So, this inextricably means that there will be two calculations of the capability index. The one which yields the lowest value is the one we are going to compare it with the standard value of 1.67. As an extra information, process capability index is influenced by the way the process data are collected, that is, the process view. Process view can be defined in terms of the time frame, sampling method (sampling frequency, size...) used to obtain process data.
Monday, April 5, 2010
Industrial Training First Day (5-4-2010)
Today was a mentally exhausting beginning to my industrial training. Time seems not to budge. Luckily I was sufficiently pertinacious in keeping myself awake from 8.30am till 5.30pm.
Customarily, the first day would be designated for introductions. I was first introduced to the organizational chart by my supervisor, Mr. Melvin. He is an amicable and helpful person. His concise, animated and lucid explanations not only alleviated my anxiety, but also had imbued me with fundamental information about the operation of NXP Semiconductor.
Basically, this company is a breakaway department from Philips which specializes in semiconductor manufacturing. Some of the terms mentioned were totally unfamiliar as those were not covered in any of the lectures in UNITEN before. For instance, wafer fab, die bonding, wire bonding and so forth.
As an brief overview, this company industrial processes can be divided into three categories, namely front end, middle end and back end. In the front end process, silicon ingots of exceedingly low impurities will undergo sawing process, culminating in disc-like wafer fabs. Each piece of this wafer usually impregnates thousands of individual units, deemed as dies. Each die will then undergo die bonding process, to be followed by wire bonding process.
Then, in the mid end section, molding and plating of the dies on lead frames will be conducted. While in the back end section, processes involved are trimming, testing, marking, forming, taping, to be followed by prepacking, quality assuring and finally shipping or delivery of end products.
Apart from the aforementioned introduction narrated by Mr. Melvin, he also took me for several horizon-broadening visits to their assembly lines in which I was inundated with awe as the sight of sophisticated, impeccable machines appeared in front of me. Every employee that enters this assembly line, which composed of front end, mid end and back end, is required to wear special attire. This is to mitigate the baneful effects of our body's electrostatic charges on the semiconductors.
Besides that, I was asked to look up the internet as well as the company's intranet to gain knowledge on semiconductor manufacturing involving wafer fabs. I was also introduced to miscellaneous probable defects of the semiconductor. For example, exposed wires, contaminated dies, cracked wafers, pimples, scratched wafers and so forth.
That's all from me. I hope there could be more breaks in between the working hours as it was really mentally tormenting for me to stare at the computer whole day long. For your information, the lunch break is the only break we are having, and it is only just a paltry 45 minutes.
Customarily, the first day would be designated for introductions. I was first introduced to the organizational chart by my supervisor, Mr. Melvin. He is an amicable and helpful person. His concise, animated and lucid explanations not only alleviated my anxiety, but also had imbued me with fundamental information about the operation of NXP Semiconductor.
Basically, this company is a breakaway department from Philips which specializes in semiconductor manufacturing. Some of the terms mentioned were totally unfamiliar as those were not covered in any of the lectures in UNITEN before. For instance, wafer fab, die bonding, wire bonding and so forth.
As an brief overview, this company industrial processes can be divided into three categories, namely front end, middle end and back end. In the front end process, silicon ingots of exceedingly low impurities will undergo sawing process, culminating in disc-like wafer fabs. Each piece of this wafer usually impregnates thousands of individual units, deemed as dies. Each die will then undergo die bonding process, to be followed by wire bonding process.
Then, in the mid end section, molding and plating of the dies on lead frames will be conducted. While in the back end section, processes involved are trimming, testing, marking, forming, taping, to be followed by prepacking, quality assuring and finally shipping or delivery of end products.
Apart from the aforementioned introduction narrated by Mr. Melvin, he also took me for several horizon-broadening visits to their assembly lines in which I was inundated with awe as the sight of sophisticated, impeccable machines appeared in front of me. Every employee that enters this assembly line, which composed of front end, mid end and back end, is required to wear special attire. This is to mitigate the baneful effects of our body's electrostatic charges on the semiconductors.
Besides that, I was asked to look up the internet as well as the company's intranet to gain knowledge on semiconductor manufacturing involving wafer fabs. I was also introduced to miscellaneous probable defects of the semiconductor. For example, exposed wires, contaminated dies, cracked wafers, pimples, scratched wafers and so forth.
That's all from me. I hope there could be more breaks in between the working hours as it was really mentally tormenting for me to stare at the computer whole day long. For your information, the lunch break is the only break we are having, and it is only just a paltry 45 minutes.
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