Silicon Labs reveals roadmap for MEMS

by R. Colin Johnson
Contributing Editor, MEMS Investor Journal

Silicon Laboratories Inc. (NASDAQ: SLAB) acquired MEMS oscillator maker Silicon Clocks for $22 million last week, even though it already markets CMOS-only oscillators that do not require a mechanical time base. In an exclusive interview with MIJ, Silicon Labs revealed that the acquisition has wider aims than just hedging is bets on MEMS versus CMOS for timing chips.

"We felt that MEMS could make an important addition to our timing chip family," said Mike Petrowski, general manager of Silicon Labs timing solutions. "But we are a diversified mixed-signal chip maker and MEMS is inherently a mixed-signal sensor technology, so let your imagination run wild."

The target of both CMOS-only and MEMS timing chips is the elimination of quartz as a mechanical time base. Now Silicon Labs is the only commercial chip maker with both MEMS and CMOS expertise.

"We're taking both sides of the MEMS versus CMOS argument," said Petrowski. "From a reliability and simplified manufacturing standpoint, both technologies have promise to make a big impact -- it’s just a matter of using the right tool for the right job."

According to Petrowski, MEMS technology has the frequency stability that rivals quartz, but CMOS-only timing chips can be manufactured very inexpensively, allowing Silicon Labs to extend its timing chip family at both the high and low end simultaneously. But since the Silicon Clocks acquisition brought to Silicon Labs 20 patented processes for fabricating MEMS on top of CMOS, it plans to use MEMS for more than just making time.

"Our obvious initial focus is to extend our timing chip offerings, but we think we can leverage our mixed signal expertise to do a variety of things with MEMS -- not just timing," said Petrowski. "Think in terms of integrating other MEMS structures on a CMOS chip to enable applications outside timing -- some sort of sensor, for example. The possibilities are starting to get pretty interesting."

Petrowski said that development efforts are already under way, but that new MEMS device announcements will not be made until next year.