Plasma Potential Measurements and Strain Effects in Epitaxial GAN Grown on AlN Buffered Si(111) by Radio Frequency Reactive Sputtering

Abstract

AbstractWe have grown epitaxial GaN thin films on A1N buffered Si(lll) by radio frequency glow discharge sputtering. GaN growth direction strains and GaN E2 optical phonon energies are measured. At the same growth temperature, plasma potentials of the radio frequency glow discharge in which GaN is grown, GaN growth rate, and strain in GaN increase systematically as a function of increasing input power. The measured GaN E2 optical phonon energy scales with GaN lattice strain. Our results indicate the presence of significant intrinsic stresses in epitaxial GaN films and point to the importance of plasma characteristics in controlling the physical properties during plasma assisted thin film deposition.