Shallow Carrier Trap Levels in GaAsN Investigated by Photoluminescence

Abstract

Shallow carrier trap levels in GaAs 1-x N x epi-layers are investigated by photoluminescence in 4.2-300K. There are 3 emissions in PL spectra of near-band-edge of GaAsN based on peak decomvolution. The existence of these peaks is evidence of carrier localization at near-band-edge. We clarified the energy levels of the peak on low energy side and its intensity of this peak increase with increasing N composition up to x = 0.0038. This behavior is similar to degradation of electrical property. This carrier trap center may act as scattering center in GaAsN. We determined band gap energy by photoreflectance technique.