Dependence of self-heating effect on passivation layer in AlGaN/GaN HEMT devices

In this paper, the effect of passivation layer on thermal resistance of AlGaN/GaN HEMT devices is investigated. In AlGaN/GaN HEMT devices, it is investigated that how this passivation layer influences the heating manner of the device. The total thermal resistance including passivation layer thermal resistance is calculated. The effect of self-heating on current-voltage qualification of AlGaN/GaN HEMT device is inspected. The results of this investigation show that device self-heating is strongly affected by the thickness of passivation layer and thermal conductivity of materials utilized in device structure. Mostly, passivating process by SiO₂ and Si₃N₄ is used to decline the density of trap levels on device surface. In AlGaN/GaN HEMT devices, it is investigated that increasing passivation layer thickness and type of passivation material strongly influence on hot spot temperature.