title: Measurement of band offsets in Y2O3/InGaZnO4 heterojunctions.
abstract: The valence band discontinuity (ΔE(v)) of Y2O3/InGaZnO4 (IGZO) heterojunctions was measured by a core-level photoemission method. The Y2O3 exhibited a band gap of -6.27 eV from absorption measurements. A value of ΔE(v) = 0.44 ± 0.21 eV was obtained by using the Ga 2p3/2, Zn 2p3/2 and in 3d5/2 energy levels as references. Given the experimental bandgap of 3.2 eV for the IGZO, this would indicate a conduction band offset ΔE(c) of - 2.63 eV in the Y2O3/IGZO heterostructures and a nested interface band alignment.
authors.forename: Jong Cheon
authors.initials: JC
authors.lastname: Park
authors.forename: Kyeong-Won
authors.initials: KW
authors.lastname: Kim
authors.forename: Brent P
authors.initials: BP
authors.lastname: Gila
authors.forename: Eric S
authors.initials: ES
authors.lastname: Lambers
authors.forename: David P
authors.initials: DP
authors.lastname: Norton
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Pearton
authors.forename: Fan
authors.initials: F
authors.lastname: Ren
authors.forename: Jin Kon
authors.initials: JK
authors.lastname: Kim
authors.forename: Hyun
authors.initials: H
authors.lastname: Cho