Micro-oven-controlled MEMS oscillator with electrostatic tuning for frequency trimming

This paper reports a micro-oven-controlled silicon oscillator with electrostatic tuning for frequency trimming for the first time. The resonator is degenerately doped with phosphorous and micro-oven controlled to achieve ppm level temperature stability, whereas the frequency is tuned by electrostatic force to compensate for fabrication tolerance. This study demonstrates that the resonant frequency of a MEMS resonator can be tuned to 38 ppm, which is equivalent to the line width variation of 0.25 μm. while achieving a temperature drift of less than 1.8 ppm from -40 °C to 85 °C.