Effect of plasmon-LO phonon coupling on the mobility of GaN

Wurtzite gallium nitride (w-GaN) is a wide band-gap, polar semiconductor. Its wide use in electronic devices makes understanding of carrier transport critically important. Traditionally, the phonon-limited electron mobility calculation is carried out assuming an equilibrium phonon gas, although the electron-phonon interaction invariably leads to nonequilibrium distributions of both the electron and the phonon systems. Using a recently developed method [1] which treats the transport of the coupled plasmon-LO phonon modes in conjunction with the electron transport, we calculate the carrier mobility of w-GaN for various doping levels and at different temperatures. Density functional theory is combined with analytic models to obtain the electron-phonon scattering rates. The mobility is calculated by performing an iterative solution of the coupled electron and plasmon-LO phonon Boltzmann transport equations.

[1] Hauber, A., & Fahy, S. (2017). Physical Review B, 95(4), 045210.