82 / 2021-06-30 14:56:24

Study on Piezoresistive Behavior of Amorphous Carbon Films and Their Application in MEMS Force Sensor and Stretchable Strain Sensor

amorphous carbon films, piezoresistive behavior, applications

Combining with their outstanding mechanical, electrical properties, chemical inertness and large piezoresistive effect, amorphous carbon (a-C) films have been proposed as one promising sensitive material, especially in some harsh environments. In this work, a series of a-C films were produced using PVD method, their piezoresistive behavior, performances of MEMS sensors and stretchable strain sensors were investigated. Results showed that piezoresistive gauge factor (GF) of a-C depended on their sp² content and the sp² cluster size, a-C based MEMS force sensor had a sensitivity of 9.8 V/V/mN and non-linearity about 2.0% FS in the testing range of 0–210 mN, a-C/PDMS stretchable strain sensor displayed a maximum gauge factor of 746.7 and strain range up to 0.5, with a satisfactory repeatability for 5000 cycles