Cathodoluminescence studies of carrier concentration dependence for the electron-irradiation effects in p-GaN

Abstract

Electron-irradiation increase of nonequilibrium carrier lifetime was studied as a function of hole concentration in Mg-doped GaN. Temperature-dependent cathodoluminescence (CL) studies yielded activation energies of 344, 326, 237, and 197meV for samples with hole concentrations of 2×1016, 9×1016, 3×1018, and 7×1018cm−3, respectively. The systematic decay of activation energy with carrier concentration was found to be consistent with Mg acceptors, indicating the involvement of the latter levels in irradiation-induced lifetime changes.