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24 The PCB Design Magazine • June 2017 you save. We had to switch to a third facility in Northern China, which is basically employ- ees made up of North Koreans. And there we found the discipline it takes. You can do this in Japan, but outside of Japan nobody else can really make this thing work except for these Ko- rean workers and we got to 99.85%. Now we're shipping 10,000,000 modules a month that use both embedded capacitors and resistors and ICs because they're so small. The surface is taken up with an active device either with the MEMS microphone, the optical sensor for the camera, or the antennas for the WI-FI, and things like that. But this is all mostly dedicated to the mo- bile phone market, which is great, but most of the readers of The PCB Magazine aren't in the mobile phone market. Matties: Aren't those also in applications like hearing aids and other medical devices? Herrera: We have seen them in applications where they're calling them micro-fluidics or micro-fluids, where they need to heat up a liq- uid and move it through these small channels on a MEMS sensor. That's an application in the medical field and that's the one that comes to mind. Others had medicine delivery applica- tions; the heater would heat up the medicine and help push it through a patch. Brandler: Since resistors are heaters, we see a greater demand for, usually, flex heaters in which the dielectrics are extremely thin because you want the heat to go right through it. I'm sure it applies to our competitors as well, be- cause it's very thin; the advantage of using these as heaters is that it takes very little power to get a very fast temperature rise because there's so little thermal mass—you can get a fast tempera- ture rise even though there's not a lot of heat. There are applications for that and it's not really big, even though Manuel is involved with de- signing this. I would say in terms of percentage of our business it's very low compared to the other things we were speaking about. Herrera: Maybe the reason it's gaining a little traction is due to the way these devices are be- ing built. They're more modular. Imagine a motherboard for a computer—this has actually been done—with embedded resistors, say 700 embedded resistors on the whole motherboard. Now, our process is a subtractive process, so all the area that's not being used as resistors is basi- cally etched off; essentially 95% of that layer is gone and only 5% is left for the resistors. Since they're all termination resistors, we decided to make a small interposer board and put all the termination resistors on it. Now in- stead of getting four motherboards on a panel, we'll get hundreds of these small interposer boards and that will be used to attach the IC; then that'll go on to the motherboards. What they did is essentially use a lot more of the resis- tive material. And the same idea is what we're Figure 6: OhmegaFlex rectangular and circular heaters. A DEEP LOOK INTO EMBEDDED TECHNOLOGY