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September 25, 2019 | Mike Creeden, CID+, InsulectroEstimated reading time: 2 minutes
I recently spoke with Insulectro’s Chris Hunrath and DuPont’s Steven Bowles at the DuPont Technology and Innovation Center in Sunnyvale, California. We discussed a variety of topics related to flex design, including the support structure that’s needed in flex design, the everchanging world of flex materials, and the need for working with a flex fabricator as early as possible in the flex design cycle.
Mike Creeden: Welcome, gentlemen. Today, I’m with Chris Hunrath of Insulectro, the vice president of technology, and Steven Bowles, flex circuit applications engineer at DuPont. Today, we’re visiting the DuPont Silicon Valley Technology and Innovation Center in Sunnyvale, California. This is an impressive facility.
To provide some background on myself, I’m now the technical director of design and education at Insulectro. I’m an EPTAC IPC master instructor teaching CID and CID+ programs, and I’m also the founder of San Diego PCB—a company I sold to Milwaukee Electronics Screaming Circuits in 2016.
Today’s designers and engineers are finding the need for using flex, rigid-flex, and printed electronics in all market segments. As we start approaching the next generation of electronics, materials matter. So, the IPC Designers Council Executive Board created and recommended a definition for the profession of design layout that would be published in the first page of the IPC-2200 series designer specifications. The definition explains what a designer needs to do to make revision 1 work. It has been referred to as “The Designer’s Triangle,” explaining three perspectives for success. The first perspective is DFS (designing for solvability). Truly solving HDI with micro devices as best you can by using any of the CAD tools in front of you. The next perspective for success that the designer needs to accomplish is DFP (design it for performance). As we route our circuits the copper plays a part, and the materials that exist between the copper play a significant part. I’m hoping Chris can address that. The third perspective is DFM (designing for manufacturability), and much of that is why this Technology and Innovation Center exists at DuPont. I’m hoping Steven can tell us about that because people need to be able to discover what the next step is as they consider flex design and how it can be built.
Steven, can you tell us a little bit about your background and your role at DuPont?
Steven Bowles: I’m a flex circuit applications engineer at DuPont Silicon Valley Technology Center. I’ve been with DuPont for a little over a year now. Before that, I manufactured flex, rigid, and rigid-flex circuits for about 15 years. I worked at a few different board shops, all domestically, in multiple processes and engineering positions. I’ve also participated in IPC, am a current member of over a dozen standards development groups, and chair three of them.
Creeden: Next, can you tell us about yourself, Chris?
Chris Hunrath: I’ve worked both on the fabrication side and on the supply side of the PCB industry. I started with multilayers back in 1983 and never looked back. I have been working with the supply side about two-thirds of my career and with Insulectro for the past 18 years. I work a lot with our customers, especially on the flex circuit side, by helping them select the right materials and with the processes in the fabrication of flexible circuit boards.
To read this entire interview, which appeared in the August 2019 issue of Design007 Magazine, click here.
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