The surfactant effect of In during the growth of GaN by molecular beam epitaxy was investigated. It was found that the presence of In modified the diffusion kinetics in the growing surface; thus leading to the persistent reflection high-energy electron diffraction intensity oscillations which were characteristic of layer-by-layer growth. Electron microscopic studies revealed drastic modifications, of the GaN structure, which were associated with the presence of In during growth. When grown in the presence of In, the GaN exhibited an intense band-edge luminescence which was free of the 3.41eV component that was characteristic of defects which were associated with growth under N-rich conditions.

Improved Quality GaN Grown by Molecular Beam Epitaxy using In as a Surfactant F.Widmann, B.Daudin, G.Feuillet, N.Pelekanos, J.L.Rouvière: Applied Physics Letters, 1998, 73[18], 2642-4