title: Evolution of the SrTiO3-MoO3 Interface Electronic Structure: An in Situ Photoelectron Spectroscopy Study.
abstract: Modifying the surface energetics, particularly the work function of advanced materials, is of critical importance for a wide range of surface- and interface-based devices. In this work, using in situ photoelectron spectroscopy, we investigated the evolution of electronic structure at the SrTiO3 surface during the growth of ultra-thin MoO3 layers. Because of the large work function difference between SrTiO3 and MoO3, the energy band alignment on the SrTiO3 surface is significantly modified. The charge transfer and dipole formation at the SrTiO3-MoO3 interface leads to a large modulation of work function and to apparent doping in SrTiO3. The measured evolutions of electronic structure and upward band bending suggest that the growth of ultra-thin MoO3 layers is a powerful tool with which to modulate the surface energetics of SrTiO3, and this surface engineering approach could be generalized to other functional oxides.
authors.affiliation: †Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
authors.forename: Yuanmin
authors.initials: Y
authors.lastname: Du
authors.affiliation: ‡, Advanced LSI Technology Laboratory, Corporate Research and Development Center, Toshiba Corporation, Kawasaki 212-8582, Japan.
authors.forename: Hai Yang
authors.initials: HY
authors.lastname: Peng
authors.affiliation: ⊥Department of Physics, Hangzhou Normal University, Hangzhou 310036, PR China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Mao
authors.affiliation: #Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710072, PR China.
authors.forename: Ke Xin
authors.initials: KX
authors.lastname: Jin
authors.affiliation: †Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.affiliation: †Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: ∇Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, PR China.
authors.forename: Xing Yu
authors.initials: XY
authors.lastname: Gao
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: †Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
authors.forename: Tom
authors.initials: T
authors.lastname: Wu
keywords: MoO3; SrTiO3; charge transfer; photoelectron spectroscopy; work function