GaN Based Carbon Dioxide Sensor

Abstract

AlGaN/GaN high electron mobility transistor based carbon dioxide sensor with ZnO nanorods as a sensing material was fabricated. The response of the device to carbon dioxide gas was characterized at elevated measurement temperature. The transistor showed an increase in drain current upon 500 ppm CO2 due to the enhanced electron channel at the interface of AlGaN and GaN from 150°C. Reliable repeatability to cyclic exposures of various concentrations of carbon dioxide gas was observed. Also, effect of humidity on sensing behavior was investigated.