Interdiffusion process in the InSe/Pt interface studied by angle-resolved photoemission

The electronic structure of the InSe/Pt interface has been studied by angle-resolved and X-ray photoemission measurements. From these results, it has been found that Pt incorporates into the InSe lattice at initial stages of Pt deposition, acting as a surface acceptor-like which tends to turn the interface into intrinsic. Beyond certain Pt submonolayer coverage, the band-bending process appears to be controlled by localized states appearing close to the Fermi level. The appearance of these states has been attributed to a reaction-like mechanism between diffused Pt and InSe atoms. For this interface, it has been found that a final electronic barrier of ∼1.2 eV is formed, close to that expected for an abrupt InSe/Pt Schottky barrier. Nevertheless, the atomic structure of the interface is far from that expected for an ideal Schottky interface.