title: Schottky barrier formation and band bending revealed by first- principles calculations.
abstract: The formation of a Schottky barrier at the metal-semiconductor interface is widely utilised in semiconductor devices. With the emerging of novel Schottky barrier based nanoelectronics, a further microscopic understanding of this interface is in high demand. Here we provide an atomistic insight into potential barrier formation and band bending by ab initio simulations and model analysis of a prototype Schottky diode, i.e., niobium doped rutile titania in contact with gold (Au/Nb:TiO2). The local Schottky barrier height is found to vary between 0 and 1.26 eV depending on the position of the dopant. The band bending is caused by a dopant induced dipole field between the interface and the dopant site, whereas the pristine Au/TiO2 interface does not show any band bending. These findings open the possibility for atomic scale optimisation of the Schottky barrier and light harvesting in metal-semiconductor nanostructures.
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, Göteborg, SE-412 96, Sweden.
authors.forename: Yang
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, Göteborg, SE-412 96, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Hellman
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, Göteborg, SE-412 96, Sweden.
authors.forename: Yurui
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Beijing Computational Science Research Center, Beijing, 100094, China.
authors.forename: Shiwu
authors.initials: S
authors.lastname: Gao
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, Göteborg, SE-412 96, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Käll