A MEMS piezoelectric in-plane resonant accelerometer based on aluminum nitride with two-stage microleverage mechanism

In this paper, we firstly present a MEMS (micro-electromechanical systems) piezoelectric in-plane resonant accelerometer with two-stage microleverage mechanism. Double ended tuning fork (DETF) resonators are actuated and sensed by piezoelectric transduction with aluminum nitride (AlN). A configuration with centrosymmetrically-distributed DETF resonators and two-stage microleverage mechanisms are proposed in the piezoelectric resonant accelerometer. The optimized configuration maximizes the length of DETF resonator in a given area and the leverage mechanism amplifies the inertia force. Both these two features enhance the sensitivity of the resonant accelerometer. The sensitivity of the device is 28.4 Hz/g and the relative sensitivity is 201 ppm/g (at the base frequency around 140.7 kHz), which are 57% and 268% higher than previously reported data. The nonlinearity characteristic and features of differential structure are also studied.