An Oven-Controlled MEMS Oscillator (OCMO) With Sub 10mw, ± 1.5 PPB Stability Over Temperature

This work presents a 20.2 MHz, 1.1 Million quality factor silicon MEMS resonator with sub 10mW ovenization power and ±1.5 ppb (parts-per-billion) frequency offset over 100 °C temperature range. This combination of ppb-stability, mm-scale size and mW power is unprecedented in the timing industry. The micro-oven design embedded within the fully encapsulated device layer provides excellent thermal isolation and low power operation while obtaining high yield and shock resistance. The control signal for oven is derived from the difference between the temperature coefficient of frequency (TCf) of dual modes within a single resonator body. This work exceeds the prior work [1] by improved heater design to <; 2x better thermal isolation, signal conditioning and shock survivability without offset.