Wednesday 31 October 2012

Week 3 - 31 Oct 2012 - Wed

12th day at SSMC.

Today was tiring, have been staring at the computer for the whole day. I was supposed to do some calculations of data using Microsoft Excel's formula but before doing the calculations, I need to identify and categorize the data by the different wafer defect types.

However, not all data are categorized clearly in detail. Some of the data have their defect type stated in the description part but not all. Thus, those that have their defect type stated in the description column, I had an easier time in categorizing them.

On the other hand, most of the data were not clearly described and to confirm and check them, I had to, one by one, look for the individual files (using the Lot ID), open up the files and check  the disposition. If the disposition doesn't state, then I need to check the pictures of the wafer.

Still, it's my 1st time identifying wafer defect types, it took me the whole day. And I still couldn't managed to finish it. Hope to finish it tomorrow.

Tuesday 30 October 2012

Week 3 - 30 Oct 2012 - Tue

11th day at SSMC.

Today finally got the software Tera Term, for creating the charts, installed onto my computer. I'm not quite sure if this 'Tera Term' is the one same as what I had encountered during Sensors Technology and Application practical lesson but things I've done using this 'Tera Term' is different from the one I had for my practical lesson. So, I guess, they should be different.

Anyway, I don't have much to post for today and I can only say that I have been trying to create trial chart for practice today. As there are certain requirements to be set up and create by other people before I can do the actual charts.

Besides, the grouping of points of the different areas for each measurement have to be reconsidered. We just realized that there are still things to be taken into considerations before we start to create the charts.

So, I guess I'm back to preparation stage.

I really do not have much to say so I think I will end here. Hope that tomorrow will have more things to share (but I pretty much doubt so).

Monday 29 October 2012

Week 3 - 29 Oct 2012 - Mon

Start of the week again, 10th day at SSMC.

I have basically finish all the preparation for creating the charts. What's left is to wait for the IT technicians to installed the software into my computer and then I get to start creating charts. But of course, I have to learn to use the software as well.

Since most of the preparations are done, today, as a start, I did the 'Free Time Task' that was given to me last Thursday. (It's called free time task as Miss Pascale said to do it during my free time; when I had nothing to do.)

This 'Free Time Task' is to calculate, using the Microsoft Excel's formula, certain data for Miss Pascale. I am supposed to calculate the followings using Excel's formula to pick and calculate columns and rows of data:


I have explored Excel's formula and Help to decide which formula to use and finally had solved the task with 3 formula, 'DSUM', 'DCOUNT' and 'COUNTIFS'.

The 'COUNTIFS' formula, as I have mentioned in my previous post, I am familiar with it. Just have to select the right criteria ranges and the associated ranges and the result will be out.

Today, I have learnt 2 new formula, 'DSUM' and 'DCOUNT'. Both formula require database (list of related data), field (the column label used) and the criteria.

These are examples of the formula I had done today:

=DSUM('Output Qty'!$1:!1048576,"qty",N$1:O$2)

=DCOUNT('Output Qty'!1:1048576,"qty',Tabulations!M1:O2)

=COUNTIFS('Output Qty'!$B:$B,Tabulations!E$2,'Output Qty'!$S:$S,Tabulations!F$3,'Output Qty'!$X:$X,1)

Another point that I have learnt today. For criteria that do not want to include certain points, use something like "<>apple", then data that are apple will not be included in the calculations.

Like as I've mentioned in the starting of this post, I need to learn the software before I can create the charts and today, I had attended a training lesson on the basic steps of creating the charts.

I am looking forward to create the charts, of course, after the software is being installed in my computer first...

Thursday 25 October 2012

Week 2 - 25 Oct 2012 - Thu

Ninth day at SSMC, last day of the week.

These few days I have been finding the Max and Min values for the particle count, air velocity for different areas. As for today, I've done the similar task for Ionization. Difference is, in ionization, there are 2 parameters and each parameter has both positive (+) and negative (-) measurements. The 2 parameters are Decay Time and Offset Voltage.

However, beside Max and Min, today had to find the Average and Range values too. Thus, the data to be calculated is quite a lot. The picture below shows how I had organised the values but I am not suppose to reveal any company data. So the picture only shows the format without any data values.


After which, I have also calculated Max and Min values for the particle counts for the other areas to cut down the total number of charts to be created.

And finally, after so many days of calculating the Max and Min values for all the possible areas, the total number to charts we will be creating is 48 charts. From previously 191 charts, we had managed to cut down to 48 charts, I feel very satisfied. (^^)

Today, I had explored Microsoft Excel's Macro functions. I have created, using the Macros, buttons (after being clicked) that will link me to another worksheet. Although, they (the Macros that I have created) are not very useful, I still feel very satisfied.

Today is only Thursday but is the last working day of the week. I have realized the importance of public holiday now. Lol... (^^)

Wednesday 24 October 2012

Week 2 - 24 Oct 2012 - Wed

Eighth day at SSMC.

Today, Miss Pascale showed me some database of SSMC's in the excel files and I was supposed to improve on the existing files using pivot tables and macros. However, we find that the two functions were not very useful and we were able to use certain formula to replace them for the same purposes.

However, using which formula is the problem I met today. I've tried using 'COUNTIF', 'SUMIF', 'IF', 'AND', 'HLOOKUP', and 'MATCH'. In the end, I solve the "mystery" using the 'COUNTIFS' formula.

Some FAILED formula examples:

=IF(Defect!$D:$D=AOQ!$A9,IF(Defect!$N:$N=AOQ!$B$3,IF(Defect!$O:$O=AOQ!$C$4,COUNTIF(Defect!$D:$D,$A(),0),0),0)

=AND(IF(Defect!D:D=AOQ!A17,1,0),IF(Defect!N:N=AOQ!B3,1,0))

=COUNTIF(Defect!D:D,(AND(IF(Defect!D3:D34=AOQ!A17,Defect!N:N=AOQ!D3,Defect!O:O=AOQ!B4),1,0)))

The Finally successful formula I had used to solve my problem today:

=COUNTIFS($A:$A,$E18,$B:$B,F$12,$C:$C,F$13)

Today, I have also found out the Max and Min values for some points and we were able to combine the areas into one chart. Thus, the total number of charts required has lowered to 111 charts.

Time flies?? Tomorrow is last day of work for this week... Hope that everything goes smoothly... (^^)

Tuesday 23 October 2012

Week 2 - 23 Oct 2012 - Tue

Seventh day at SSMC.

Today, on and off was using the computer to do work. And why did I say 'on and off'? Lol. It's because the computer was not working for some time. Thus, today had wasted some time doing nothing. >.< ( But, I did try to keep the slacking time to minimum by reading the handouts given. ;P)

I thought that I was going to do what I had mentioned in yesterday's post,that is, listing out the exact points for the ESD tests. However, just this morning, I realized that the points for the ESD tests were always randomly chosen. Hence, I (somehow) cut down my workload... XP

Yesterday, after listing out the points for the support areas, I found out that there were very little points in each area. After discussion with Miss Pascale, she had decided that if the maximum (Max) and the minimum (Min) value of the areas' data are within the similar range, then we are able to combine those areas into 1 chart. And this will cut down the number of charts to be created.

And so, I had, for the whole morning, been checking the Max and Min value for each area (using excel). It wasn't very hard, however, there were too many data. So in a way, it took me awhile to finish.

Meanwhile, after lunch, my computer broke down... Here comes my reading time. And in fact, I've been using electrostatic discharge (ESD) the term quite often but I had never known its exact meaning. So, reading is really good... Below are what I've learned today:

Electrostatic discharge (ESD) is the transfer or movement of charge between objects that are of different electrical potentials. It is caused by static electricity.

Static electricity is a stationary (non-moving) electrical charge and it is caused by imbalance of elctrons on the surface of materials.

Imbalance of electrons occurs when materials either lose or acquire electrons.

Some time in the afternoon, when my computer is back on track, I continued to do the same task for the ESD tests. Finding the Max and Min value for each area of each test. The ESD data were more then that of the support areas. I had a tedious afternoon to evening. Fortunate thing is, I manged to finish the ESD portion just before work ends.

I did not expect today to have so much things to say. Hope tomorrow will be better. This week is one short week. 2 more working days and break!! Friday, I'm so looking forward to you!!! (^^)

Monday 22 October 2012

Week 2 - 22 Oct 2012 - Mon

First day of a new week, sixth day at SSMC.

Today, I did not do much things but the task that was given to me was enough for me to do for the whole day. Was it because that I'm too slow?

The task that I was assigned today was to check and confirm all the points of places for taking measurements for particle, air velocity and ionization.

Under the 3 main categories (particle, air velocity and ionization), there are places with many points for measurement to be taken. It could be in the same place but the exact points are different. And I have to check if the points are still in use as some points are either 'down' or 'shut off'. Some points are Thus, it took me the whole day to finish listing every point out.

Currently, I have estimated the total number of charts to be created is 191 charts. This includes particle, air velocity, ionization and 2 other measurements which are field voltage and electrostatic discharge (ESD) monitoring.

Tomorrow, I will be doing what I've done for today (listing out points for the measurements) for the ESD monitoring. And then I will have to think about how I will be setting up my Real Time Charts. I have the whole of this week to think about it and to try out the charts using another software as we will only have training on the SPC program on next Monday.

Today is such short and sweet. But is it a good thing? @.@

Friday 19 October 2012

Week 1 - 19 Oct 2012 - Fri

Fifth day at SSMC, last day of the week.

This morning, I have been asked to regroup the points under 'scanners' as what I have done in the fab yesterday turns out to be unproductive. Yesterday, I have set the group as 'scanners' and locations as each individual points for measurement. However, after transferring the settings to the charge plate monitor, the MA will be requiring to press the 'NEXT' button until the desired location before pressing the 'START' button. Miss Pascale said that this is unproductive and will be a waste of time and battery of the charge plate monitor.

Thus, I have been thinking for better solutions for this problem. Unfortunately, I still did not managed to have a perfect solution. Ideas that I had did not solve the entire problem. My ideas only managed to lessen the number of time pressing the button but the exact points locations couldn't be shown.

And after lunch, fab activity again! Never thought that I would get to go to the fab so many times. Today is the third time time this week. (^^)

Today was at fab to try out some setting for the particle counter monitor, similar to what I have done for the charge plate monitor yesterday. After finished setting up the monitor, I have to take photos on the steps (in detail) of operating the monitors, for both the particle counter monitor and the charge plate monitor. This is for future ease of reference.

That's all for today and this week. Tomorrow is Saturday. Weekends!!~~ (^^)


Thursday 18 October 2012

Week 1 - 18 Oct 2012 - Thu

Fourth day at SSMC.

Today started off with what I had done yesterday which was not mentioned in yesterday's post. I had identified and calculated the points for 'scanners' and 'corridors' from the whole fab. And after consultation form Miss Pascale, we have decided to have 2 charts for each category.

The current total number of charts that we will be requiring to create is 161 charts. The photo below shows the number of charts for the different categories.


Miss Pascale said that before I can create the charts, I have to understand the process and procedures of the Manufacturing Assistance (MA) taking measurements. This is to ensure the charts that I create can be valid under any circumstances. Thus, I need to know all possible scenarios that might happen.

So, I am required to visit the fab again. And I did. This afternoon, I went to the fab again but this time was alone. And even with Miss Pascale's verbal directions given, I am still confused... In the end, Miss Pascale drew me a 'map'. XP


I went there to see how the charge plate monitor works and to try setting up 'groups' and 'locations' in the PC and transfer to the charge plate monitor. The fab personnel, Azizah, was very friendly and kind to me. She showed me the steps and was helping me with the try-out as they had never done that before. And after some time, the set up was successful. (^^) The photo below shows the operator's guide for the charge plate monitor and because I was going in the fab which is of cleanroom environment, normal paper cannot be brought in. Hence, another copy is printed using cleanroom papers.


My last bit of work for today was to list out all points for future ease of reference. However, no photo taken. ;P That's all for today, I guess... Anyway, tomorrow is Friday! My first Firday since attachment started... ;P

Wednesday 17 October 2012

Week 1 - 17 Oct 2012 - Wed

Third day at SSMC.

Today, I categorized the different monitoring items for the Electrostatic Discharge (ESD) tests by the areas that these tests will be performed in. I have organised my work in a table format, hoping that it will be easier for people to view it.



I have also read up notes and report on the different monitoring items and tests to have better understanding on them. It was pretty hard to understand them at first as there were many acronyms used. For example, HBM stands for Human Body Model and CPM stands for Charge Plate Monitoring.

Thus, when I had finished all required work, I went on to read the reports and take down notes on all the acronyms used for future reference. During reading of the reports, I found that some of were seen yesterday during the fab visit (with Miss Pascale's explaining them to me).

With that, I find that sometimes visual exposures allow me to remember things better. (^^)

Tuesday 16 October 2012

Week 1 - 16 Oct 2012 - Tue

Second day at SSMC.

Today, I spent my time in listing out the areas in SSMC that require environment monitoring and I get to familiarize with the different lab areas that SSMC has.

For example, all support rooms are located on the third floor. A support room is part of a fab but it is outside the main room. It also does not consist of a sub fab like the main room does. I also got to know that the Mask Incoming Quality Control Room (MIQC) is a place to store reticle and stocker is a storage room for wafer.

After listing out the areas that require environment monitoring, I carried on grouping the areas by the measuring units and the parameters which includes particle monitoring, air velocity monitoring and ionization monitoring.

After which, I made drawings and divided the ball room / photo area into 8 zones and in each zone, calculations had been made to check the number of measurement data to be collected per year. Similar stuff is also done for the Chemical Mechanical Planerisation (CMP) area.The photo below shows the drawing and calculations that I had done. (^^)



A rough calculation had been made and I found out that we will have to create around 150 charts or even more... What a challenge!

The most exciting part of today's experience is the FAB visiting!!! Instead of reading about the different areas from papers, I actually get to see them REAL. And the different equipment and tools used to measure particle, air velocity and ionization too. Things that I've only get to see from TV, I get to experience them today...

Have you experience wearing a jumpsuit before entering the fab? Not to mention the cap, gloves and shoes. (^^)

Monday 15 October 2012

Week 1 - 15 Oct 2012 - Mon

Reported to Systems on Silicon Manufacturing Co. Pte. Ltd. (SSMC) today for first day of my attachment.

We had a short tour in the company and followed by videos watching to know more about SSMC. We also had briefing from Miss Katherine from the Human Resource department and I am attached to the Quality Systems & Information Management (QSIM) division, Quality & Reliability Assurance (QRA) department and Quality Engineering Management (QEM) sector. (^^)  

After which, I met up with my supervisor, Miss Pascale Tan, who is the Principal Engineer from the QRA department, and we proceeded to the office... 

Miss Pascale mentioned to me that I will be doing a project on setting up a Real Time Environment Monitoring Statistical Process Control (SPC). 

The photo below shows the notes and handbooks that I have looked and read through the whole of today to have a better understanding of the concept of environment monitoring which includes particles, air velocity and ionization. Though I have read through them several times, I am still doing my best in understanding them. Fortunately, I have Miss Pascale for consultation thus I had managed to get the big idea of the complex concept. 


Miss Pascale mentioned that tomorrow she will be showing me the SPC charts and I am really looking forward to it. I hope that I will be able to help Miss Pascale in setting up a Real Time Environment Monitoring Statistical Process Control (SPC) for SSMC.