New values of the Ag-n-GaP potential barrier

Abstract

Surface-barrier structures of the Ag-GaP type based on high-quality epitaxial n-GaP layers with n=(0.5–30)×1016 cm−3 were studied. It was found that the potential barrier height depends on the method of surface treatment prior to the metal deposition and correlates with the structural nonideality coefficient and the intermediate layer thickness. For high-quality structures with a reverse current below 10−14 A, the barrier height is ϕ=1.55±0.04 eV. For structures with a relatively thick intermediate layer, the barrier may reach up to ϕ=1.7±0.07 eV. The dependence of the barrier height on the method of the GaP surface treatment is related to the absence of rigid pinning of the Fermi level on the GaP surface.