title: Carrier Transport at Metal/Amorphous Hafnium-Indium-Zinc Oxide Interfaces.
abstract: In this paper, the carrier transport mechanism at the metal/amorphous hafnium-indium-zinc oxide (a-HIZO) interface was investigated. The contact properties were found to be predominantly affected by the degree of interfacial reaction between the metals and a-HIZO; that is, a higher tendency to form metal oxide phases leads to excellent Ohmic contact via tunneling, which is associated with the generated donor-like oxygen vacancies. In this case, the Schottky-Mott theory is not applicable. Meanwhile, metals that do not form interfacial metal oxide, such as Pd, follow the Schottky-Mott theory, which results in rectifying Schottky behavior. The Schottky characteristics of the Pd contact to a-HIZO can be explained in terms of the barrier inhomogeneity model, which yields a mean barrier height of 1.40 eV and a standard deviation of 0.14 eV. The work function of a-HIZO could therefore be estimated as 3.7 eV, which is in good agreement with the ultraviolet photoelectron spectroscopy (3.68 eV). Our findings will be useful for establishing a strategy to form Ohmic or Schottky contacts to a-HIZO films, which will be essential for fabricating reliable high-performance electronic devices.
authors.affiliation: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University , Jeonju, Chonbuk 561-756, Korea.
authors.forename: Seoungjun
authors.initials: S
authors.lastname: Kim
authors.affiliation: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University , Jeonju, Chonbuk 561-756, Korea.
authors.forename: Youngun
authors.initials: Y
authors.lastname: Gil
authors.affiliation: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University , Jeonju, Chonbuk 561-756, Korea.
authors.forename: Youngran
authors.initials: Y
authors.lastname: Choi
authors.affiliation: Department of Nano-Optical Engineering, Korea Polytechnic University , Siheung 429-793, Korea.
authors.forename: Kyoung-Kook
authors.initials: KK
authors.lastname: Kim
authors.affiliation: Division of Materials Science, Korea Basic Science Institute , Daejeon 305-333, Korea.
authors.forename: Hyung Joong
authors.initials: HJ
authors.lastname: Yun
authors.affiliation: Division of Materials Science, Korea Basic Science Institute , Daejeon 305-333, Korea.|Analysis Center for Research Advancement, Korea Advanced Institute of Science and Technology , Daejeon 34141, Korea.
authors.forename: Byoungchul
authors.initials: B
authors.lastname: Son
authors.affiliation: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University , Jeonju, Chonbuk 561-756, Korea.
authors.forename: Chel-Jong
authors.initials: CJ
authors.lastname: Choi
authors.affiliation: School of Semiconductor and Chemical Engineering, Semiconductor Physics Research Center, Chonbuk National University , Jeonju, Chonbuk 561-756, Korea.
authors.forename: Hyunsoo
authors.initials: H
authors.lastname: Kim
keywords: HIZO; Ohmic; Schottky; Schottky−Mott; carrier transport; contact; interfacial reaction