Ultra-Thin, Temperature Stable, Low Power Frequency References
We have developed a MEMS based thin (<100 μm), temperature stable (< 1 parts-per-billion per degree Celsius (ppb/°C)), low power (<10 mW), frequency reference. Traditional high stability oscillators are based on quartz crystals. While a mature technology, the large size of quartz crystals presents important mission barriers including reducing oscillator thickness below 400 μm, and low power temperature stabilization (ovenizing). The small volume microresonators are 2 μm thick compared to 100’s of microns for quartz, and provide acoustic/thermal isolation when suspended above the substrate by narrow beams. This isolation enables a new paradigm for ovenizing oscillators at revolutionary low power levels <10 mW as compared to >300 mW for oven controlled quartz oscillators (OCXO). The oven controlled MEMS oscillator (OCMO) takes advantage of high thermal isolation and CMOS integration to ovenize the entire oscillator (AlN resonator and CMOS) on a suspended platform. This enables orders of magnitude reductions in size and power as compared with today's OCXO technology.