Temperature-dependent mobility modeling of GaN HEMTs by cellular automaton method

GaN HEMTs are expected to achieve better device performance for microwave applications. The cellular automaton method is effective for predicting the transport characteristics of the two-dimensional electron gas, which is the key to the HEMT device performance. To predict the mobility of two-dimensional electron gas, it is necessary to consider the physics of the subbands. Since the traditional powerful Monte Carlo method selects the electron scattering mechanism by random numbers, it is necessary to suppress statistical problems to obtain a stable solution. We confirmed that our approach that combines the Poisson-Schrodinger and the cellular automaton method enables seamless and stable mobility calculations over a wide temperature range including low temperatures. In this paper, the temperature-dependent electron mobility of GaN HEMT calculated with and without interface roughness scattering model is studied.