GaN Growth with Low-Temperature GaN Buffer Layers Directly onSi(111) by Hydride Vapour Phase Epitaxy

Abstract

GaN films are grown on Si(111) with low-temperature GaN (LT-GaN) layersas buffer layers by hydride vapour phase epitaxy (HVPE). The depositiontemperature of the LT-GaN layers is changed from 400 to 900 degrees C.When the LT-GaN layer is deposited at 600 degrees C, GaN films show onlyc-oriented GaN (0002) and have the band edge emission at 365 nm with noyellow luminescence bands. The results indicate that the LT-GaN layercan effectively block the unexpected Si etching by reactive gas duringthe GaN growth. However, the surface roughness of these GaN films grownon Si(111) is larger than that of GaN films on c-plane sapphire.