18 things Fabless start-ups should look for in a Yield Management System


Do you work for a Fabless start-up? Are you ramping up?

If so, you need data-analysis tools for your production data. You will struggle without them. You have two options for yield management analysis. You may decide to hire an engineer (or team of engineers) whose job is to transfer the data from datalogs to a spreadsheet, then generate reports. Or, you could invest in a system that takes care of that for you. A good YMS generates information automatically from the datalogs and creates reports. Your engineering team will spend less time inputting data, and more time solving problems.

If you decide to start using a semiconductor yield management system, there are several key areas to look at. Here they are:

  1. Customized reports: Can the yield management system create customized reports, with the information you want to see? Many systems have pre-determined reports that can't be customized. The best systems allow you to create reports from the data you need to see. During production ramp-up, your needs will change. You might want to see different items in the report, at different stages of production.

2. User experience: If you're going to invest in a system, you may as well invest in something that's easy to use. The look and feel of different systems vary widely. Get a system that you know your team will like to use.

3. Speed: The advantage of a YMS is that it creates reports at the touch of a button. When speaking to different providers, ask for a demo with your data so you can see how fast it is for yourself. Involve a member of the production or test team to get their opinions too.

4. Security: As technology advances, people are more and more concerned with their security. You need to ask your provider what systems they have in place to safeguard your data.

5. Safety: Is your data safe from natural disasters? If the provider is cloud-based, there is a good chance that they store the data a lot more safely than your traditional hard-copy, for example, tape.

6. Archiving: This may or may not be important to you. Many companies like to archive their data so they can access it in the future. This varies from industry to industry. But it is a feature that some companies provide. So if it is important to you, ask.

7. Scalability: As a growing company, you need a system that is comfortable handling small amounts of data as well as large amounts of data. It also needs to handle incremental increases in volume, as your company grows. Some systems can handle small amounts only. Others are best used for big-data. As a growing Fabless start-up, you need a system that can handle data of all sizes or it could slow you down later on.

8. Sending reports automatically: Would you like to get a report every day or every week? Would some of your colleagues like reports more often, or none at all? Rather than generating reports yourself, some yield management systems generate them for you, as often as you like. This allows you to track your yield, bin distributions, and the performance of key tests, without even logging in.

9. Alerts: Get an alert whenever something goes amiss in production. This feature is in addition to reporting. Hopefully, you'll never need them but they are invaluable when something goes wrong. You tell it the rules and the YMS sends an alert when it needs to, any time of the day.

10. Generalities and detail: Yield management systems should give you a broad overview of what’s going on in production. They should also let you drill down into on any issues quickly. For example, yieldHUB’s system lets you see what’s happening in manufacturing. If you spot a problem, you can zoom in on the errant wafer to see where the issue is. We call it “high-level to die-level”.

11. Correlations: Will the yield management system allow you to quickly correlate issues across manufacturing? (e.g. from final test back to fab). If so, it could help your foundry with information that will improve your yield.

12. Data formats: STDF is an industry-standard. But as your company grows, you may be generating different file formats. Ask the provider what formats they can handle. If your formats are going to vary, ask the vendor how agile they are with parsing new types of data.

13. Outlier Detection: Will your YMS provider support algorithms like GDBN and DPAT for your wafer maps should you require automotive quality in the future.

14. Analysis tools: What other tools do they provide? Some have sophisticated analysis tools for test and product engineers - for example, Sensitivity Analysis and Virtual Retest to simulate changing test limits.

15. Integration: Will the system disrupt your current production flow? Or are they flexible enough to customize their solution for your needs.

16. Service: This is also a key area. Some semiconductor yield management systems are not supported by the people who wrote the software. This sometimes happens when vendors are acquired by another company. As the industry is fast-changing, you don’t want to be left with an outdated system that barely does what you want it to do.

17. Roadmap: Has your vendor a roadmap you can relate to? Ask them what their plans are for the year. This will give you an idea of where the company is going. You can use this to evaluate whether it fits your needs or not.

18. The cloud:

Cloud-based systems are revolutionizing business. Cloud-based yield management systems are equally revolutionizing yield management. They are very affordable, even for fabless start-ups. There are many advantages. One advantage is that you can store huge amounts of data, archive it, and access it from anywhere when you need to. Another is that it’s easier for your team to collaborate with each other. As it’s an online system, they can add comments as needed.

As you can see, there are a lot of areas to consider when choosing a YMS system. Using a checklist like this will help you identify if a system meets your needs or not, very quickly.