Abstract: Combining the development requirements of intelligent equipment and wireless detection system, a piezoresistive microaccelerometer with high sensitivity and resonant frequency is presented based on micro-electro-mechanical system (MEMS)technology and stress concentration. Theoretical modeling and numerical calculation are performed to specify its structure parameters. Sensor chips are fabricated by micromachining technique and tested to characterize its static and dynamic properties. Experimental results show that the sensitivity of slotted quad-beam structure accelerometer is as high as 0.424 mV/g with a 3 V power supply. Compared with the traditional quad-beam structure sensor, an increase of sensitivity by 60% is obtained, with a slight decrease of natural frequency which is still higher than 10 kHz. The introduction of stress concentration slots into quad beams promises the sensor characters by improving sensitivity remarkably and sacrificing slight natural frequency.

Key words: Accelerometer, Micro-electro-mechanical systems, Piezoresistive, Slotted quad-beam structure