Low-temperature formation of metal/molecular-beam epitaxy-GaAs(100) interfaces: Approaching ideal chemical and electronic limits

Abstract

[[abstract]]The authors report soft X-ray photoemission studies of metal/molecular-beam epitaxy (MBE)-GaAs(100) interfaces formed at low temperature. The results indicate that rectifying barrier heights are proportional to the metal work function in accordance with Schottky's original description of metal-semiconductor contacts. These results confirm the predictions of a self-consistent model of metal-semiconductor interfaces, and suggest that metal-induced gap states and native defect mechanisms are not major factors in determining the Fermi level energy at `ideal' interfaces. The authors attribute deviations from the ideal Schottky limit behavior observed for interfaces formed at room temperature to metallization-induced atomic relaxations (rather than electronic relaxations) occurring at metal-semiconductor contacts. They present a useful methodology for analyzing electronic properties at metal-semiconductor interfaces. The pronounced differences in barrier height formation between MBE vs melt-grown GaAs can evidence the role of deep states in controlling Schottky barriers at metal/melt-grown GaAs[[fileno]]2060117010073[[department]]工程與系統科學