Doping level dependence of electron irradiation-induced minority carrier diffusion length increase in Mg-doped GaN

Abstract

The electron irradiation-induced increase of minority carrier diffusion length was studied as a function of hole concentration in Mg-doped GaN. Variable-temperature electron beam induced current measurements yielded activation energies of 264, 254, 171, and 144meV for samples with hole concentrations of 2×1016, 9×1016, 3×1018, and 7×1018cm−3, respectively. This carrier concentration dependence of the activation energy for the effects of electron irradiation was found to be consistent with Mg acceptors, indicating the involvement of the latter levels in the irradiation-induced diffusion length increase.