偏压对HEMT嵌入式微加速度计电学参数的温度特性影响

摘要

The temperature effect of the high electron mohility field effect transistor ( HEMT) embedded in accelerometer was studied at different voltage bias. The results indicate that temperature coefficients of output current are difierent from each other because of the selection of voltage bias. The main reason is that the temperature effect of the drain current is determined by the combination of mobility ' s temperature coefficient and threshold voltage ' s temperature coefficient , but the two coefficiets are opposite ,and the contributions of them can be adjustable according to the quantum of selected voltage bias , so the appropriate work point can be determined, thereby reducing the temperature drift of the electrical parameters, and make the temperature coefficient of some electrical parameters to zero. Therefore, if the HEMT as a sensitive unit of the micro-sensor, it will work in a wide temperature range and resolve the measurement error caused by the temperature, so it can provide some basis to the teat at bad environment that is difficult to control the temperature.%研究了HEMT嵌入式微加速度计在不同偏压下的温度效应.研究结果表明由于选择的偏压不同,输出电流的温度系数大小不同.其主要原因是漏极电流的温度效应由迁移率的温度系数和阈值电压的温度系数共同决定,两种效应一正一负,根据选择偏压大小,可以调整各自的贡献,确定合适的工作点,从而减小电学参数的温度漂移,甚至可以使某些电学参数的温度系数为零.因此,以HEMT作为微传感器的敏感单元,可以在较宽的温度范围内工作,解决由于温度的影响所带来的测量误差,为温度难以控制的恶劣环境的测试提供一定的依据.