Modelling of temperature dependence on current collapse phenomenon in AlGaN/GaN HEMT devices

Abstract

This paper reports the studies of the temperature dependence on the current collapse behaviours of AlGaN/GaN high electron mobility transistors (HEMTs). A physical-based model is proposed to analyse the trapping and de-trapping process along the surface with the effect of temperature included for the first time. The temperature-dependent gate leakage current is treated as the source for electron trapping and it can be predicted by the proposed model quantitatively. Then the relationship of the capture cross section of the surface trap on the electric field is investigated with respect to temperature variations. By applying the Poole-Frenkel emission mechanism, the dynamics of the trapped electrons at different temperatures are described in this model. The analytical results on current recovery time-constant are then verified by comparing with the laboratory measurement as well as the numerical results obtained from Sentaurus TCAD simulations.