Barrier height at clean Au/InAs(100) interfaces Available to Purchase

Using photoelectron spectroscopy, we have reexamined the barrier height at Au/InAs(100) contacts prepared under ultrahigh vacuum conditions. The $n$-barrier height is 0.010$±$0.050 eV: the Fermi level at the interface is right at the InAs conduction band edge. This result is expected from models based on charge transfer into metal-induced gap states but contrasts with previously published experimental values. Depending on the preparation procedure, the surface of InAs(100) grown using molecular-beam epitaxy shows $c(4×4)$ or $(2×4)$ reconstruction; the barrier height, however, is independent of the surface reconstruction prior to gold deposition.