A Modeling Study of Electron Transport in GaN/AlGaN Superlattices Using Monte Carlo Simulation

Abstract

Electron transport in superlattices (SLs) is analyzed using a single‐particle Monte Carlo (MC) method. This study includes the band structure of GaN, AlN, and their alloys, utilizing a single‐electron MC approach and a three‐band model. It explores how intervalley (IV) and electron–polar longitudinal optical phonon (PLOP) scatterings influence electron velocity. A single non‐parabolic band approximation is effectively used in SL modeling, as the miniband's energy width limits electron kinetic energy, reducing IV scattering. The energy band structure of the SL is calculated using the Schrödinger equation and a Poisson solver, incorporating a single‐band model to determine the Fermi energy and characteristics of the SL miniband. Miniband dispersion is evaluated using an effective mass approximation at low energies and a non‐parabolicity factor at higher energies. The MC method is then applied to study electron transport within the miniband, revealing that for SLs with low Al content and short periods, electron behavior resembles that in bulk GaN. It is observed that negative differential mobility can occur, attributed to electron–PLOP scattering and non‐parabolicity. This approach offers a quick and effective way to research high‐field electron transport in n‐doped SLs, aiding in device design.