Crystal Growth and Optical Property of GaN on Silica Glass by Electron-Cyclotron-Resonance Plasma-Excited Molecular Beam Epitaxy (ECR-MBE)

Abstract
GaN films were grown on a silica glass substrate by electron-cyclotron-resonance plasma-excited molecular beam epitaxy (ECR-MBE). It was found that GaN films grown on silica glass exhibited stronger photoluminescence (PL) intensity than that exhibited by GaN films grown on sapphire substrates and the PL peak position was the near-band-edge emission of hexagonal GaN. In addition, the full-width at half maximum of the PL spectrum for GaN grown on silica glass was smaller than that of GaN grown on sapphire. GaN films grown on silica glass were c-oriented polycrystalline films consisting of columnar domains. It is believed that c-axis orientation and columnar growth are strongly related to the optical properties.