Suppression of hexagonal GaN mixing by As 4 molecular beam in cubic GaN growth on GaAs (0 0 1) substrates

Abstract

A mechanism of hexagonal GaN crystal-phase mixing in cubic GaN growth under As 4 molecular beam irradiation on GaAs (0 0 1) substrates has been investigated. It is found that the As 4 beam irradiation during growth of the GaN is effective for the suppression of the hexagonal GaN mixing on the {1 1 1} A planes, although it is not so effective for the {1 1 1} B planes. The results strongly indicate that the high-quality cubic GaN layers will be obtained in the MBE growth by the As 4 beam irradiation combined with the formation techniques of the atomically flat surfaces such as the high-temperature atomic hydrogen treatment.