Kubo Minoru

Effects of low energy ion bombardment on GaAs molecular beam epitaxy

Abstract The effects of low-energy ion bombardment on molecular beam epitaxy (MBE) growth have been studied by low-energy ion scattering (LEIS). LEIS is a novel in situ MBE monitoring system which is highly sensitive to the atomic structure of topmost layers. Noble ion bombardments during the MBE growth of GaAs strongly affect the morphology and crystalline qualities of grown films. We have observed characteristic LEIS profiles, and surface structures such as diatomic steps and disordering by ion bombardment have been analysed. Although the effects of ion bombardment on electrical and optical properties of grown films have not been clarified yet, we have confirmed positive effects of the ion bombardment on the surface morphology. We discuss the mechanism of morphology improvements, and demonstrate the feasibility of ion bombardment during the MBE growth together with the usefulness of LEIS for structure analyses.