A novel study of the resistance of thermopile for thermoelectric MEMS microwave power sensors

In order to study the effect of the resistance of thermopile on the output performance of thermoelectric microelectromechanical system (MEMS) microwave power sensors, the relationship of the electron mobility and the resistance in n+‐type GaAs is studied, and the reason why the resistance of thermocouple changes with the input microwave power and frequency is analyzed. The experimental results show that in the range of 8 ∼ 12 GHz, the return loss of the sensor is less than −27.75 dB, and the sensitivity of the sensor is 0.055 mV/mW@10 GHz. The resistance of thermopile shows a downward trend with the frequency. With the input power range from 0 to 300 mW, the resistance of thermopile increases from 55.51 to 71.17 kΩ, and it has good linearity. Therefore, this work has a certain reference value for improving the output performance of thermoelectric microwave power sensors.