Interface chemistry of metal-GaAs Schottky-barrier contacts

Abstract

A survey of the metal-semiconductor interface chemistry for GaAs and seven metals, Ag, Al, Au, Cr, Fe, Sn, and Ti, by using x-ray photoemission spectroscopy (XPS) is reported. Sn and Ag each form an abrupt inert interface with GaAs. Au, Al, Fe, Cr, and Ti each form a chemically reacted nonabrupt interface with a trend for increasing dissociation of GaAs in the order listed. Also reported is the first observation of epitaxial Fe growth on GaAs.