Design and Application of a High Sensitivity Piezoresistive Pressure Sensor for Low Pressure Conditions

Sensors

Huiyang Yu²  Jianqiu Huang¹ 

[1] Key Laboratory of MEMS of the Ministry of Education, Southeast University, No.2 Sipailou, Xuanwu District, Nanjing 210096, China; E-Mail:;College of Computer Science and Technology, Nanjing Tech University, No.30, South Puzhu Road, Pukou District, Nanjing, 211800, China

关键词: piezoresistive;    pressure sensor;    stress concentration;    low pressure;   

DOI  :  10.3390/s150922692

来源: mdpi

【 摘 要 】

In this paper, a pressure sensor for low pressure detection (0.5 kPa–40 kPa) is proposed. In one structure (No. 1), the silicon membrane is partly etched to form a crossed beam on its top for stress concentration. An aluminum layer is also deposited as part of the beam. Four piezoresistors are fabricated. Two are located at the two ends of the beam. The other two are located at the membrane periphery. Four piezoresistors connect into a Wheatstone bridge. To demonstrate the stress concentrate effect of this structure, two other structures were designed and fabricated. One is a flat membrane structure (No. 2), the other is a structure with the aluminum beam, but without etched silicon (No. 3). The measurement results of these three structures show that the No.1 structure has the highest sensitivity, which is about 3.8 times that of the No. 2 structure and 2.7 times that of the No. 3 structure. They also show that the residual stress in the beam has some backside effect on the sensor performance.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.