Local vibrational modes of H complexes in Mg-doped GaN grown by molecular beam epitaxy

Abstract

Local vibrational modes (LVM’s) in Mg-doped GaN grown by molecular beam epitaxy have been studied by Raman scattering. Besides Mg local vibrational modes, several local mode peaks associated with hydrogen complexes are observed in the region around 2200 cm−1 and peaks assigned to carbon-hydrogen complexes are also detected in the region around 2900 cm−1. These modes arise from the presence of unintentional carbon and hydrogen impurities in the sample, which was corroborated by secondary ion mass spectroscopy measurements. Raman scattering evidence of local vibrational modes of the C-H complex in GaN is reported. The behavior of the LVM’s associated with the hydrogen and carbon impurity complexes with annealing temperature is also reported.