title: Modulation-Doped In2O3/ZnO Heterojunction Transistors Processed from Solution.
abstract: This paper reports the controlled growth of atomically sharp In2O3/ZnO and In2O3/Li-doped ZnO (In2O3/Li-ZnO) heterojunctions via spin-coating at 200 °C and assesses their application in n-channel thin-film transistors (TFTs). It is shown that addition of Li in ZnO leads to n-type doping and allows for the accurate tuning of its Fermi energy. In the case of In2O3/ZnO heterojunctions, presence of the n-doped ZnO layer results in an increased amount of electrons being transferred from its conduction band minimum to that of In2O3over the interface, in a process similar to modulation doping. Electrical characterization reveals the profound impact of the presence of the n-doped ZnO layer on the charge transport properties of the isotype In2O3/Li-ZnO heterojunctions as well as on the operating characteristics of the resulting TFTs. By judicious optimization of the In2O3/Li-ZnO interface microstructure, and Li concentration, significant enhancement in both the electron mobility and TFT bias stability is demonstrated.
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors.forename: Dongyoon
authors.initials: D
authors.lastname: Khim
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors.forename: Yen-Hung
authors.initials: YH
authors.lastname: Lin
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors.forename: Sungho
authors.initials: S
authors.lastname: Nam
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Faber
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.
authors.forename: Kornelius
authors.initials: K
authors.lastname: Tetzner
authors.affiliation: Cornell High Energy Synchrotron Source, Wilson Laboratory Cornell University, Ithaca, NY, 14853, USA.
authors.forename: Ruipeng
authors.initials: R
authors.lastname: Li
authors.affiliation: Division of Physical Sciences and Engineering, King Abdullah University of Science & Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Division of Physical Sciences and Engineering, King Abdullah University of Science & Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Division of Physical Sciences and Engineering, King Abdullah University of Science & Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Xixiang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Physics and Centre for Plastic Electronics, Imperial College London, South Kensington, London, SW7 2AZ, UK.|Division of Physical Science and Engineering, King Abdullah University of Science & Technology (KAUST), Thuwal, 23955-6900, Kingdom of Saudi Arabia.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Anthopoulos
keywords: electron mobility; heterojunction transistors; metal oxides; modulation doping; semiconductors; solution processing; thin film transistors