APL, 114(2019)253502 1-4

Piezoresistive behavior of amorphous carbon films for high performance MEMS force sensors

基于非晶碳膜压阻行为的高性能MEMS压力传感器

Xin Ma, Peng Guo, Xiaoshan Tong, Yulong Zhao, Qi Zhang, Peiling Ke, Aiying Wang*

In this study, microelectromechanical systems (MEMS) force sensors based on H-free amorphous carbon (a-C) films with controlled piezoresistive behavior were fabricated by a facile magnetron sputtering technique. By adjusting the substrate bias voltage from 0 V (floating state) to –350 V, the gauge factor (GF) of the a-C film was modulated in the range of 1.4–12.1. Interestingly, the GF showed a strong dependence on the sp² content and the sp² cluster size of the film, which was consistent with the theory of thick film resistors. In addition, the sensitivity of a-C based MEMS force sensors reached 80.7 μV/V/N in the force range of 0–1.16 N, with a nonlinearity of approximately 1.3% full scale and good repeatability in over 5000 test cycles.

URL :

 https://doi.org/10.1063/1.5096225