使用混合式（電容式/壓阻式）感測機制的微加速計

In this paper, we want to introduce a novel micro accelerometer with a hybrid piezoresistive/capacitive sensing technique. In general, micro accelerometer has only one type sensing technique. In this paper, we report, to the best of our knowledge, the first micro accelerometer using a hybrid capacitive/piezoresistive sensing technique. Here, we will introduce two micro accelerometer, in-plane and out-of-plane, designed by us. For our novel high-g in-plane micro accelerometer, the measured capacitance change in the capacitive sensing mode is 0.028 pF under 690 g. The measured voltage change in the piezoresistive sensing mode is 0.335 V under 612 g. The mechanical resonant frequency of the micro accelerometer is measured to be 4.26 kHz, i.e. < 5% deviation from the ANSYS prediction. For our z-axis out-of-plane, the maximum measured voltage change in the piezoresistive sensing mode is 0.215V under 11 g. The maximum measured capacitance change in the capacitive sensing mode is 0.26 pF under 10.3 g. The mechanical resonant frequency of the micro accelerometer is calculated to be 353 Hz.