Issue



MEMS of high sophistication


09/01/2008








Peter Singer is editor-in-chief of Small Times. He can be reached at psinger@pennwell.com.
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I set off on what I thought was a simple quest a couple of months ago, to identify a few of the most sophisticated microelectromechanical system (MEMS) devices in the world.

My quest was triggered by a talk at SEMICON West by John Foster, president of Innovative Micro Technology (Santa Barbara, CA), who was describing a bio-MEMS device designed to sort rare cells, such as stem cells. The disposable chips are wafer-level packaged with integrated 3D microfluidics and on-board reflective and refractive optics. The device lays claim to a speed record as the world’s fastest electromagnetic MEMS actuator, which accelerates from 0???1.4m/sec and back to 0 in 15??sec, averaging 12,000G, with a stroke 22??m long.

“We believe this may be the world’s most complex MEMS,” he said. A short time later, Rob O’Reilly of Analog Devices noted that his company made some pretty complex MEMS too, no doubt referring to the company’s accelerometers and gyroscopes.

This got me thinking about what MEMS might be the world’s most sophisticated, and how would one define that? Is it the device with the most moving parts? The finest geometries? The highest functionality? The fastest speed? Most challenging integration of diverse materials and components? The most value to mankind?

This issue covers a range of these types of MEMS devices, looking not only at what end applications are driving the push to make them smaller and more capable, but the manufacturing techniques required to produce them.

Marlene Bourne notes in her article “A new take on MEMS innovation” (p. 20) that current emerging market drivers aren’t necessarily coming in the form of new MEMS devices (as we’ve seen in the past), but rather, new ways to apply existing MEMS devices. She provides many examples that “offer real potential for very high unit volumes.”

Benedetto Vigna, GM of STMicroelectronics’ MEMS product division, describes MEMS used for consumer applications (p. 12). Likewise, he says it’s hard to predict the market success of these applications since some technological hurdles still exist for a big volume take-off. “However, it’s clear that all the applications could benefit from the tiny and low-power micro-machined sensors that companies are developing now for the consumer market,” he says.

And the granddaddy of all MEMS devices, the inkjet printhead, is also covered. Dick James of Chipworks takes a look at the three-color printhead device out of Hewlett Packard’s low-cost HP 60 Tricolor ink cartridge launched earlier this year (p. 16). If you haven’t thought of inkjet printheads as overly sophisticated, this article may change your mind???these MEMS devices must endure explosive cavitation and ionization and potentially corrosive chemicals. The best part of all: it’s easily the most high-volume MEMS device today. “While HP is not thought of as a MEMS manufacturer (in the sense of accelerometers and gyroscopes), they actually lead the world in MEMS sales, with sales over $850M in 2007, driven by their printer chips,” James points out.

If you have examples of MEMS devices that are highly sophisticated, and/or poised for high-volume growth, please let me know and we’ll include them in a future issue or online at www.smalltimes.com. You can reach me at psinger@pennwell.com or 603/891-9217.