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20 SMT007 MAGAZINE I MAY 2020 to use the Koh Young SPI sys- tem they have at their shop to verify their pastes. Again, I don't have any end-users that I know of using the 008004 parts yet, but we're giving them a system via the aSPIre3 and 10-micron lens resolution to be able to inspect those smaller parts. Johnson: The equipment and material suppliers have proven that they can deliver the functionality needed for the current smallest parts of the market, even if people may not be using them yet. Welch: Yes, but the caveat to that is that when- ever we do something in the lab with a bunch of engineers involved, you can oftentimes get very good results. You don't always get those results when you put it into manufacturing. Since joining Koh Young in April 2016, I've visited about 50 customers delivering our two- to three-day SPI and print process character- ization training program. People can't print those small parts until they improve the disci- pline of their process. For a number of custom- ers, it seems the operators have hijacked the SPI process. The engineers aren't there or don't like to go out to the line except when there are serious issues. Many times, the process engi- neers aren't watching over the process like they should or don't know the process as well as they should, so there will be a reality check when they move to smaller and smaller parts. Johnson: Is it fair to say that the control of the inspection processes on the manufacturing floor with the manufacturing operators who are under one set of incentives for part of their job that may be at odds with being accurate and getting good yields, and not having field failures later? Welch: That's correct. A lot of engineers don't want to be called to the line if they don't have to be, so they leave it to the operators or process tech- nicians. If they don't visit often enough, then the oper- ators are going to hijack the process and do whatever they think is right. I've stood there many times watching an operator pass boards that should have been failed. I call those "wall of shame" examples, where they've opened up the inspection tolerances, or the opera- tors are doing whatever they want to do, and then prod- ucts are escaping SPI. They have a great tool in SPI, but they're not using the tool as best they can. That will definitely be a chal- lenge when they get to the smaller parts. Johnson: Let's paint a possible scenario then. Right now, maybe it's working, they're getting by, and they're doing okay purely by accident. As they move to smaller and smaller parts, that's going to break at some point. What should they be looking for, and how do you fix it? Welch: SPI reveals the sins of the process. I'm trying to teach people how to use the tool as best they can, as well as tools and techniques for analyzing the data. It's also important not to be driven by just defects but by the para- metric data that shows them how well the pro- cess is performing in terms of process capabil- ity. Then, it's about improving the process and not just trying to turn off SPI defects. Johnson: This must be a challenge. You're pro- viding products that could help customers see fewer field failures and better yield, but by default, it's exposing the dirty laundry in the process. That can be potentially embarrassing or even job threatening. How do you change that from a threat to a benefit? Brent Fischthal: When Ray delivers these engagements to our customers, he helps them Ray Welch

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