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Title: Homogeneous double-layer amorphous Si-doped indium oxide thin-film transistors for control of turn-on voltage

Abstract

We fabricated homogeneous double-layer amorphous Si-doped indium oxide (ISO) thin-film transistors (TFTs) with an insulating ISO cap layer on top of a semiconducting ISO bottom channel layer. The homogeneously stacked ISO TFT exhibited high mobility (19.6 cm{sup 2}/V s) and normally-off characteristics after annealing in air. It exhibited normally-off characteristics because the ISO insulator suppressed oxygen desorption, which suppressed the formation of oxygen vacancies (V{sub O}) in the semiconducting ISO. Furthermore, we investigated the recovery of the double-layer ISO TFT, after a large negative shift in turn-on voltage caused by hydrogen annealing, by treating it with annealing in ozone. The recovery in turn-on voltage indicates that the dense V{sub O} in the semiconducting ISO can be partially filled through the insulator ISO. Controlling molecule penetration in the homogeneous double layer is useful for adjusting the properties of TFTs in advanced oxide electronics.

Authors:
;  [1];  [1];  [2];  [3];  [4]; ;  [5]
  1. International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan)
  2. (Japan)
  3. MANA Foundry and MANA Advanced Device Materials Group, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044 (Japan)
  4. Department of Nanotechnology for Sustainable Energy, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)
  5. Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)
Publication Date:
OSTI Identifier:
22597791
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIR; ANNEALING; DESORPTION; DOPED MATERIALS; HYDROGEN; INDIUM OXIDES; LAYERS; MOBILITY; MOLECULES; OXYGEN; OZONE; THIN FILMS; TRANSISTORS; VACANCIES

Citation Formats

Kizu, Takio, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Tsukagoshi, Kazuhito, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Aikawa, Shinya, Research Institute for Science and Technology, Kogakuin University, Hachioji, Tokyo 192-0015, Nabatame, Toshihide, Fujiwara, Akihiko, Ito, Kazuhiro, and Takahashi, Makoto. Homogeneous double-layer amorphous Si-doped indium oxide thin-film transistors for control of turn-on voltage. United States: N. p., 2016. Web. doi:10.1063/1.4959822.
Kizu, Takio, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Tsukagoshi, Kazuhito, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Aikawa, Shinya, Research Institute for Science and Technology, Kogakuin University, Hachioji, Tokyo 192-0015, Nabatame, Toshihide, Fujiwara, Akihiko, Ito, Kazuhiro, & Takahashi, Makoto. Homogeneous double-layer amorphous Si-doped indium oxide thin-film transistors for control of turn-on voltage. United States. doi:10.1063/1.4959822.
Kizu, Takio, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Tsukagoshi, Kazuhito, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp, Aikawa, Shinya, Research Institute for Science and Technology, Kogakuin University, Hachioji, Tokyo 192-0015, Nabatame, Toshihide, Fujiwara, Akihiko, Ito, Kazuhiro, and Takahashi, Makoto. 2016. "Homogeneous double-layer amorphous Si-doped indium oxide thin-film transistors for control of turn-on voltage". United States. doi:10.1063/1.4959822.
@article{osti_22597791,
title = {Homogeneous double-layer amorphous Si-doped indium oxide thin-film transistors for control of turn-on voltage},
author = {Kizu, Takio, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp and Tsukagoshi, Kazuhito, E-mail: KIZU.Takio@nims.go.jp, E-mail: TSUKAGOSHI.Kazuhito@nims.go.jp and Aikawa, Shinya and Research Institute for Science and Technology, Kogakuin University, Hachioji, Tokyo 192-0015 and Nabatame, Toshihide and Fujiwara, Akihiko and Ito, Kazuhiro and Takahashi, Makoto},
abstractNote = {We fabricated homogeneous double-layer amorphous Si-doped indium oxide (ISO) thin-film transistors (TFTs) with an insulating ISO cap layer on top of a semiconducting ISO bottom channel layer. The homogeneously stacked ISO TFT exhibited high mobility (19.6 cm{sup 2}/V s) and normally-off characteristics after annealing in air. It exhibited normally-off characteristics because the ISO insulator suppressed oxygen desorption, which suppressed the formation of oxygen vacancies (V{sub O}) in the semiconducting ISO. Furthermore, we investigated the recovery of the double-layer ISO TFT, after a large negative shift in turn-on voltage caused by hydrogen annealing, by treating it with annealing in ozone. The recovery in turn-on voltage indicates that the dense V{sub O} in the semiconducting ISO can be partially filled through the insulator ISO. Controlling molecule penetration in the homogeneous double layer is useful for adjusting the properties of TFTs in advanced oxide electronics.},
doi = {10.1063/1.4959822},
journal = {Journal of Applied Physics},
number = 4,
volume = 120,
place = {United States},
year = 2016,
month = 7
}
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