N-plasma assisted MBE grown GaN films on Si(111)

Abstract

GaN films were grown by rf-plasma assisted molecular beam epitaxy on nitrified Si(111) surfaces. Scanning tunneling microscopy (STM), low energy electron diffraction (LEED), and X-ray photoelectron spectroscopy (XPS) have been used to characterize the structural and chemical properties of the GaN films. The XPS results show that GaN growth can be initiated only at temperatures below 650 °C. LEED indicates an improvement of the crystalline quality after introduction of a crystalline Si3N4 interface layer. This is confirmed by STM, where an atomically resolved 3 × 3 reconstruction for thin GaN films is observed as well as a smooth growth morphology