Key Laboratory of Electronics Engineering College of Heilongjiang Province, Heilongjiang University, Harbin 150006, China.
Sensors (Basel). 2020 Sep 3;20(17):4988. doi: 10.3390/s20174988.
In order to improve the output sensitivity of the piezoelectric acceleration sensor, this paper proposed a high sensitivity acceleration sensor based on a piezoelectric metal oxide semiconductor field effect transistor (MOSFET). It is constituted by a piezoelectric beam and an N-channel depletion MOSFET. A silicon cantilever beam with Pt/ZnO/Pt/Ti multilayer structure is used as a piezoelectric beam. Based on the piezoelectric effect, the piezoelectric beam generates charges when it is subjected to acceleration. Due to the large input impedance of the MOSFET, the charge generated by the piezoelectric beam can be used as a gate control signal to achieve the purpose of converting the output charge of the piezoelectric beam into current. The test results show that when the external excitation acceleration increases from 0.2 g to 1.5 g with an increment of 0.1 g, the peak-to-peak value of the output voltage of the proposed sensors increases from 0.327 V to 2.774 V at a frequency of 1075 Hz. The voltage sensitivity of the piezoelectric beam is 0.85 V/g and that of the proposed acceleration sensor was 2.05 V/g, which is 2.41 times higher than the piezoelectric beam. The proposed sensor can effectively improve the voltage output sensitivity and can be used in the field of structural health monitoring.
为了提高压电加速度传感器的输出灵敏度，本文提出了一种基于压电金属氧化物半导体场效应晶体管（MOSFET）的高灵敏度加速度传感器。它由压电梁和 N 沟道耗尽型 MOSFET 组成。采用具有 Pt/ZnO/Pt/Ti 多层结构的硅悬臂梁作为压电梁。基于压电效应，当压电梁受到加速度时会产生电荷。由于 MOSFET 的输入阻抗很大，因此压电梁产生的电荷可用作栅极控制信号，以实现将压电梁的输出电荷转换为电流的目的。测试结果表明，当外部激励加速度从 0.2g 增加到 1.5g，每次增加 0.1g 时，在 1075Hz 的频率下，所提出的传感器的输出电压的峰峰值从 0.327V 增加到 2.774V。压电梁的电压灵敏度为 0.85V/g，所提出的加速度传感器的电压灵敏度为 2.05V/g，是压电梁的 2.41 倍。所提出的传感器可以有效地提高电压输出灵敏度，可用于结构健康监测领域。
