Anomaly and intrinsic capacitance behaviour over temperature of AlGaN/GaN/SiC and AlGaAs/GaAs HEMTs for microwave application

In this paper, we report anomaly and intrinsic capacitance behaviour over temperature of AlGaN/GaN/SiC and AlGaAs/GaAs high electron mobility transistors using on wafer measurement up to 50 GHz. Differences are observed; most notably that the trend of the intrinsic capacitances behaviour with temperature of the two device technologies are completely different. This anomaly continues for the other device parameter such as threshold voltage, two-dimension electro gas sheet carrier densities as well. These results are valuable for the future design optimizations of the advanced GaN and GaAs based monolithic microwave integrated circuit operating at high frequency and temperature.