One of the important data fields on the STDF is the test number (TEST_NUM for the PTR, FTR and MPR records) and unfortunately it is oftentimes taken for granted by test developers. The test number is an ideal index for data analysis tools because it is stored as an integer and can be more efficient for the software when used as an index versus using the test name. For humans also, looking up for a test number can be faster vs. reading lengthy test names.

Test developers should make sure that test numbers are unique so that data analysis software and humans can use it as a reliable reference. Also, the test number assigned to the test should not change even if some tests are skipped or added dynamically. Even if the user simply exports the STDF data into Excel, having unique and consistent test numbers would be helpful in organizing the data for analysis.

Yield management, analysis and information systems would also greatly benefit from unique test numbers because these will have a small field (a few bytes for integer) to be used as an index. On database systems like MySQL, integer indices are much smaller vs. string indices. So if these systems can use the test number as an index, then queries can be faster and storage more efficient. The user is therefore more productive as he or she can get things done faster.

If yield analysis software cannot reliably determine a unique identifier for a test, data from two ore more tests can get mixed up and can affect analysis results.

Sure, there are ways around this on the parsing side but the best approach from the get-go is to make sure the test program generates unique test numbers. FloorVision, for example, already incorporates several methods of generating unique test numbers in case the STDF or any other datalog file doesn’t have them.

There are over 767,000 dice involved. Semiconductor data analysis doesn’t get more efficient than this. Email Mfg Vision info{at}mfgvision{dot}com for more information and transform how your engineers work with data.

Do you find it difficult to communicate quickly enough with your subcon or foundry in Asia should a yield issue arise?

How do you share the information necessary to get a plan of action in place? Could it take days, even weeks?

With our private cloud solution “FloorVision”, you can provide your subcon or foundry with a license which allows them to collaborate on-line with your engineers in, for all intents and purposes, real-time should the need arise.

For example, say you discover a test which is failing and you discover from the charts and tables that it’s failing on one site in the handler only. No need to send the raw data back to the subcon for their analysis. Just choose the subcon from a drop-down and share the charts and tables on-line with your comments. The subcon will receive the email straight away and review exactly what you are seeing. After they have fixed the issue, they will also be able to review the new results and share them back with you.

Subcon Analysis is Limited to their own Material

Of course if you have several subcons, you won’t want one subcon to see material manufactured in another subcon. You also won’t want them to interfere with the production database, except to add comments. That is all taken care of.

The third party licensing for your subcons and foundries which is available with our private cloud YMS system FloorVision will help you reduce the need for conference calls, even travel and help you get to mature yields more quickly. It will even help you and your subcon get to know each other better through near real-time positive collaboration.

Ensuring Efficient Worldwide Engineering Collaboration

Diodes Incorporated is one of the world’s leading manufacturers of high-quality application specific standard products, comprising discrete, logic and analog semiconductor devices, serving global consumer electronics, computing, communication, industrial and automotive markets.

Operating large development centers in three continents and a major manufacturing center in Shanghai, China, the company selected MFG Vision’s FloorVision web-based semiconductor yield management system to ensure high-efficiency worldwide engineering collaboration.

Supporting Diodes’ global yield management and data analysis needs, FloorVision provides the company with a user friendly private cloud service that incorporates fast, numerically sophisticated and highly visual engineering tools.

The Gage R&R tool for analog test correlation analysis is just one of the many tools used collaboratively by Diodes’ product, test, QA and process engineers around the world and on a daily basis.

Enabling data collected in the manufacturing center to be compared statistically and visually against data collected in the regional development centers, the tool generates live reports, which are shared instantly around the world for analysis.

The following illustrates a typical interactive chart comparing development center data, shown by the red and green traces, with manufacturing center data, shown by the blue trace.

Providing all of the numeric- and chart-based tools required for a complete measurement system and product performance analysis, the FloorVision tool suite can scrutinize data by individual tester, DUT and socket and keeps a consistent check on the performance of golden reference units over time.

Through highly focused engineering collaboration supported by the FloorVision system, product test release timescales have been reduced, equipment control improved and debugging processes accelerated.

Kevin Robinson, Analog Test Engineering Manager at Diodes Incorporated said:

“The truly collaborative nature of the FloorVision system has led to some very positive changes in the way in which we work together globally to address engineering challenges.  In a highly competitive business environment, engineering resources need to be maximized and that’s exactly what we’re achieving here.”

If you are considering a desktop solution, even ones which purport to be web-enabled, you may wish to consider the following questions:

• Does the analysis package look like it’s designed by product/test engineers or designed by IT people?
• Is your old data going to be available to you on-line going back years?
• Are you going to be able to save your work on-line and go back to it at any time in the future?
• Are you going to be able to easily invalidate rubbish data?
• Is fab data automatically linked up with probe or test data of the same material for one-click correlation analysis?
• Can you run characterization and other advanced analysis such as Gage R&R in a single click?
• Can you add comments to a datalog or a lot?
• Can you analyze from a computer or tablet or smartphone with no additional software needed, just broadband?
• Can you do Reticle Analysis in one click?
• Can you get alerted by the system if you have a paremetric problem or bin problem?
• Can you add calculated tests to datalogs?
• Can you  create on-line projects, eg for a yield improvement effort, for later sharing or presentation with colleagues?
• Can you analyse hundreds of datalogs without having to download them to your own computer first?
• Can you upload schematics and pinouts to help with analysis?

The answer to every one of the above questions is YES for FloorVision, Mfg Vision’s state-of-the-art YMS solution.

A product engineer in China recently needed to understand why FloorVision was showing certain pins in a high volume product were failing intermittently in production over the previous few days. She looked at the pinout in the datasheet, spotted something and highlighted the bottom right corner of the chip where the failing pins were clustered. She uploaded the edited image to FloorVision and after sharing with her colleagues back in the States, her suggestion of a fix was approved by the lead test engineer. She set-up a report in FloorVision to automatically email herself and the lead test engineer daily on the performance of the parameter. When everything seemed under control a couple of weeks later, she set up an exception alert to email her if this parameter failed at all again.

This type of collaboration happens every day with our customers. There is no exchange of raw data (e.g. STDF) needed. The collaboration is real-time analysis and information, and the teams, though in different states, countries or continents, get to know and respect each other’s skills because sharing is real-time with no set-up time needed even to see detailed analyses of hundreds of datalogs which could be equivalent to many GB of original raw data. No more “throwing the ball over the wall” or no requirement any more for formal weekly meetings to get things progressing. Progress happens quietly and relentlessly throughout each day and working relationships solidify over the private FloorVision cloud.

“The purchase of licenses for FloorVision in 2010 is proving to have been a smart decision by SensL as this is an ideal data analysis and yield management system for our needs.

We would highly recommend Mfg Vision’s FloorVision as a cost-effective and powerful solution for managing and analyzing semiconductor test data. Having all the results on-line (as opposed to in a user’s desktop) in a secure database with speedy analysis tools, many available in a single click, is very convenient for the needs of a mobile workforce in a fast moving business environment.”
Liam Wall, Silicon Technology Manager, SensL, 15 Nov 2011

The Data Management Headache

A prospect was being supplied by several wafer fabs, using several assembly houses and test subcons. Engineers in Asia, the US and Europe worked together with tight schedules to release new products. Yield issues occurred but often they were not aware of these until too many wafers were started, resulting in high scrap levels.

The company found that they were reacting to yield problems rather than preventing them. The engineers in Asia were using their own tools for analysing data ftp’d to them from Europe and the US. It was a tedious task trying to correlate performance across manufacturing stages which might prevent issues in the future. Releases were often delayed through absence of data.

In May 2010 they purchased FloorVision, replacing ad hoc tools.

From Hours to Minutes

Now around 100 users from Fab, Probe, Test, Quality and Reliability have the production data they need in one place. They can share analyses in one click with remote colleagues, reducing decision times for releasing a product from one or two days to just minutes. They can correlate final test and wafer probe performance in seconds and can set personal alerts for any deviation from expected product performance in production.

They have told us that we are close to “revolutionising” their business. The engineers in different countries are getting to know each other a lot better too with greatly enhanced near real-time collaboration. FloorVision typically saves them 1-5% of Yield on high running products.

Ongoing Work

Medium to large companies like the one in this case study will have new formats every so often and new needs for data analysis. We provide immediate support for any queries from our customers or to fix any bugs. We treat every company the same, be they large or small. We monitor the data pipelines closely and make sure any processing anomalies are checked by our technicians immediately. A larger company will typically ask us to develop or tweak a parser every few months. If a company needs a particular type of report or analysis type we work with them and they are assured of a cost-effective solution to their particular need at the time.

Young people starting college in 2011 will graduate in four years time with only a memory of the PC or laptop, as they have now but a memory of the CD player, or as my parents’ generation has but a memory of the typewriter.

So when these young people enter the workplace in 2015, or more specifically in this case, the semiconductor industry, as test development or product/process engineers, do you think they will be using PC-based tools like Excel or the like? Unlikely.

It’s fairly clear considering the pace of change that they will be using cloud-based apps for everything from reporting to monitoring to analysis.

There is no need any more for tools and data for semiconductor yield analysis to be local on your PC. They are already in the Cloud, as private as you like, but still in the cloud and accessible from anywhere for your dispersed engineering teams. No need to wait till 2015.

Upgrades for maintenance purposes or for enhancements occur typically about three times a year and we work closely with an internal customer team to make this seamless. We constantly work to keep FloorVision the easiest product to use in the market, as well as the most powerful for our customers, so improvements and enhancements are constantly being worked on for the next version. Every company we meet, whether a prospect or during customer visits, enhances our product for everyone over time. Alerts for Outliers, Reticle Analysis and our Test Coverage Optimizer are recent examples of tools inspired by prospects and customers alike.

We have a ticket system integrated into FloorVision, so bug reports or feature requests are immediately communicated to our engineers. This complements what we hear at meetings and we employ a web-based system for prioritizing work based on the needs we are hearing, with bugs, should they arise, always having the highest priority in the work pipeline. Contact us at info{at}mfgvision{dot}com for information about what we have to offer and what is pencilled-in on our roadmap for 2011.