Thermal and electrical performance of AlGaAs/GaAs based HEMT device on SiC substrate

Abstract

In this paper investigation on electrical and thermal performance of the AlGaAs/GaAs HEMT device is carried out by comparing the device grown on substrates like 4H-SiC and Sapphire. The investigation was carried out based on Silvaco TCAD Atlas simulation. The DC characteristics of the device with varying ambient temperature were evaluated. A deterioration of drain current from 0.9 mA to 0.5 mA is observed as temperature rises from 300K to 500K on 4H-SiC substrate. The HEMT grown on 4H-SiC substrate has a high power dissipation, resulting in reduced temperature compared to sapphire substrate. This increases the lifetime of the device by 1000s of hours and also its overall performance. The HEMT proposed here is found to have an electrically and thermally optimal performance on 4H-SiC substrate than on sapphire.