MEMS Resonators with Extremely Low Vibration and Shock Sensitivity

MEMS resonator-based oscillators have demonstrated extreme low susceptibility to acceleration. Specifically, oscillators were built employing 100nm-gap electro-statically transduced polysilicon MEMS resonators. An oscillator based upon the Lame-mode of a square-shaped resonator anchored at four corners demonstrated a measured acceleration sensitivity of Gamma(in-plane)=2.1ppb/g and Gamma(out-of-plane)=3.8ppb/g. An oscillator referencing the same design resonator with an additional anchor at the center measured even lower acceleration sensitivity by 5x, Gamma(out-of-plane)=0.74 ppb/g. These measured values are on-par with the current low-G sensitivity quartz-based oscillators. In separately performed drop tests, these oscillators have shown only -7.7 ppm frequency deviation through an 11,000G impact, which corresponds to an acceleration sensitivity of 0.70 ppb/g. Such extremely low sensitivity to vibrations and shocks enables the use MEMS resonators in environments with extremely high accelerations such as in military and aerospace applications.