Optimum design considerations for a 3-DOF micro accelerometer using nanoscale piezoresistors

This paper presents the design optimization of high performance three-degree of freedom silicon accelerometer. The purpose of this optimization is to achieve the high sensitivity and high resolution. The optimization has been performed based on considerations of junction depth, the doping concentration of the piezoresistor, the temperature coefficient sensitivity, the noise, and the power consumption. Taking advantage of high piezoresistive effect in nanoscale piezoresistor, the cross-sectional area of the piezoresistor is fabricated to be 15x104 nm². The result shows that the sensitivity of the optimized accelerometer is improved while the resolution is comparable to previous results. The dimension of sensor is as small as 1 mm², so it is suitable for many immerging applications.