A Numerical Investigation of Heat Suppression in HEMT for Power Electronics Application

In this paper, AlGaN/GaN High Electron Mobility Transistor (HEMT) with stacked passivation (Diamond/SiN) is proposed and investigated. The implementation of stacked passivation in HEMT has been shown to be effective in suppressing self-heating effect. Under the gate-terminal, the peak channel temperature of HEMT with stacked passivation is 384 K, whereas it is 393 K for conventional HEMT. The reduction of channel temperature in the proposed device is attributed to good heat-spreading via diamond. The thermal resistance (R-TH) is extracted and it is found that R(TH)of proposed HEMT is 17% lower than that of the conventional HEMT. The transconductance of the proposed GaN-HEMT is also improved by 12%. Furthermore, the maximum drain current of 800 mA/mm at V-GS = 0 V and V-DS = 5 V is obtained for the proposed HEMT with a gate length of 0.25 mu m. The proposed device is considered as one of the most attractive candidates for future high frequency and high-power applications over a wide range of operating temperatures.