Schottky barrier diode consisting of van der Waals heterojunction of MoS2 film and PtCoO2 contact

Abstract

We investigated the synthesis of delafossite PtCoO2 crystals, performed electronic transport measurements, and researched the formation of heterojunction with layered films. The crystal was deposited onto a c-plane sapphire substrate using the vapor growth method. The in-plane resistivity (460–475 µΩcm) is comparable to that of layered materials, such as few-layer graphite, applied to electrodes. Schottky contacts were obtained between PtCoO2 and n-type MoS2; therefore, a Schottky barrier diode with a low reverse saturation current was fabricated. The Schottky barrier height (ΦB) was estimated to be 0.896 eV. The atomic scale electric dipole at the interface may contributed to achieving a large ΦB. In addition, Fermi level pinning was suppressed owing to the formation of an interface by the dry transfer method.