Energy relaxation mechanisms and mobility of electrons in n-type InN

We present a theoretical model regarding the electron-phonon interactions in n-type InN at a lattice temperature of 1.5 K. A perturbation-based model with a drifted Maxwellian distribution is used for obtaining the energy loss rates and mobility from electron-phonon scattering mechanisms as a function of electron temperature and electron concentration at electron temperature range of 1.5-500 K. We show the importance of acoustic phonon emission due to piezoelectric coupling and deformation potential scattering for energy relaxation processes at low temperature region, T-e<130 K. Above this electron temperature, the polar optic phonon emission dominates the scattering mechanism and causes the reduction of electron mobility. Two transition region were seen between piezoelectric acoustic phonon and deformation potential acoustic phonon at about T-e=35 K; and between the deformation potential acoustic phonon and polar optic phonon at T-e=130 K. The model calculation results have been compared with available experimental results and a good agreement has been obtained for the energy loss rates and mobility of electrons. Also, the polar optic phonon scattering time has been obtained about 23 fs.