Investigations of temperature-dependent interface traps in AlGaN/GaN HEMT on CVD-diamond

Abstract

In this paper we report, for the first time, the investigation of hetero-interface trapping characteristics in AlGaN/GaN with a high-electron-mobility transistor (HEMT) on a CVD-diamond using the conductance method at different temperatures (25 °C to 200 °C). Fast traps with time constants from 0.16 to 10.01 μs were identified to be the dominating traps at the AlGaN/GaN hetero-interface. The density of the traps (D T) was found to increase with temperature and was attributed to the excitation of deeper traps in the bandgap at elevated temperatures. Finally, temperature-dependent pulsed I DS-V DS measurements were taken to correlate the D T behaviour and current collapse in the device.