Electrothermal analysis of AlGaN/GaN high electron mobility transistors

Efficiency of AlGaN/GaN HEMTs used in high power, high frequency applications is thought to be limited by parasitic thermal effects. In this study, we investigate coupled electrical and thermal transport in AlGaN/GaN HEMTs using an ensemble Monte Carlo model. Calculation of the non-equilibrium phonon population reveals a hot spot in the channel that is localized at low drain-source bias, but expands towards the drain at higher bias, significantly degrading channel mobility.