Photoemission study of the formation of intimate In-InGaAs(100) contacts at room and cryogenic temperatures

Previous current-voltage studies of In contacts deposited on atomically clean (intimate) In53Ga47As(100) have indicated the potential to ''select'' barrier heights in this materials system by cryogenic processing. Soft x-ray photoemission spectroscopy was used to determine the electronic and chemical nature of these interfaces, as a function of formation temperature. Metallization at room temperature results in a predominantly three-dimensional mode of growth, accompanied by the outdiffusion of As. Low temperature metallization appears to reduce clustering and inhibit As outdiffusion. It is proposed that the distribution of surface states and the fermi level pinning position are altered by the changes that occur in the geometry and bonding of the interface at low temperature. (C) 1997 American Institute of Physics.