A Thermo-Piezoresistive Resonator with F-Q Products Over 4.5E14

This paper reports a thermo-piezoresistive resonator with a measured Quality factor of over 3 million, and f-Q products of over 4.5e14, which is the highest value compared to the state-of-the-art. The device is wafer-level hermetic encapsulated through a cap with modified glass isolated TSVs, the proposed cap is suited for packaging MEMS structures in SOI wafers, and it is first reported. For a high Q-factor, the thickness of the structure is 4.5 μm for big mechanical potential energy, a symmetrical structure is chosen for low anchor loss and an extra beam with big stiffness is added between masses for a high resonant frequency. The phenomenon that self-oscillating occurs after the harmonic response to a scanning frequency excitation signal is recorded, and the resonant frequency and amplitude jump as the increased current flows in the resonator.