N–H related defect playing the role of acceptor in GaAsN grown by chemical beam epitaxy

Abstract

The N–H related defects at 3124cm-1 are found to be acceptors in GaAsN grown by chemical beam epitaxy (CBE), by comparing the concentrations of N–H defects with those of acceptors as a function of annealing condition. The vibrations of N–H defects appear as local vibration modes at 2952, 3011, 3098, and 3124cm-1 using Fourier transform infrared (FTIR) spectroscopy. The integrated absorptions at 2952 and 3098cm-1 decrease, at 3011 cm-1 remain small, while at 3124cm-1 increases due to the annealing treatment. On the other hand, the concentration of acceptors increases with the annealing time, based on capacitance–temperature (C–T) measurement. The densities of N–H defects at 3124cm-1 and those of acceptors are almost equal independent of the annealing condition. This result suggests that the N–H defects appearing at 3124cm-1 play the role of acceptors in GaAsN grown through CBE.