Issue link: https://iconnect007.uberflip.com/i/1285883
52 DESIGN007 MAGAZINE I SEPTEMBER 2020 Feature Interview by the I-Connect007 Editorial Team Ventec International Group's Alun Morgan discusses some areas of development he has seen in the company's IMS thermal materi- als, as well as technological "hot spots" that can prove troublesome to PCB designers and engineers. He also offers advice to designers working on boards with challenging thermal properties. Andy Shaughnessy: Alun, give us the history of IMS thermal materials. Alun Morgan: Like many products, it came from a need. They have been around for some time, depending on how you categorize thermal materials, but the big starter was when LEDs suddenly became very popular. LEDs emit more efficiently than incandescent lighting, but they still generate more than two-thirds of their energy as waste heat. Suddenly, you found these fairly concentrated devices gener- ating lots of heat. Mounted on the substrates, laminates are not particularly good at thermal conduction. People were sticking heat sinks on the back, trying to deal with the heat and man- aging it some way. But that added cost. The first application for these devices was consumer or domestic lighting, such as a light bulb replacement, so the cost was a really big issue. Somebody had the bright idea of integrating a heat sink on the back of the substrate. It became part of the PCB and thus took a lot of costs away, avoided having to bolt a heat sink on the back, and enabled dealing with the thermal issue as a system approach. That was the start of it. You suddenly saw these substrates with aluminum stuck on the back. Instead of another layer of copper on the back, it was a layer of alumi- num; copper was expensive and quite dense, so aluminum was the substrate of choice. It moved fairly quickly back to DC-to-DC converters. People handling power bricks and then using inverters thought, "This is quite interesting. We can also use that." They were doing it in the past with heat sinks bolted onto the back of the PCB. It's a big advantage if you can just process something within standard PCB technology. That came around. IMS Materials for Improved Thermal Management