Interface states at the Ga–GaAs interface

Abstract

A variable-excitation energy photoemission study has been made of the occupied states near the Ga–GaAs (110) interface as the interface is formed. Using a combination of valence and core-level spectroscopy, new aspects of the interface electronic structure have been deduced. Using valence-band spectroscopy, interface states are found to appear as the Ga film is built up. Using core-level spectroscopy, one finds chemical shifts in both the Ga and As 3d levels. The As shift indicates that surface charge redistribution from the As to the Ga occurs at the interface.