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Title: Restorative effect of oxygen annealing on device performance in HfIZO thin-film transistors

Abstract

Metal-oxide based thin-film transistors (oxide-TFTs) are very promising for use in next generation electronics such as transparent displays requiring high switching and driving performance. In this study, we demonstrate an optimized process to secure excellent device performance with a favorable shift of the threshold voltage toward 0V in amorphous hafnium-indium-zinc-oxide (a-HfIZO) TFTs by using post-treatment with oxygen annealing. This enhancement results from the improved interfacial characteristics between gate dielectric and semiconductor layers due to the reduction in the density of interfacial states related to oxygen vacancies afforded by oxygen annealing. The device statistics confirm the improvement in the device-to-device and run-to-run uniformity. We also report on the photo-induced stability in such oxide-TFTs against long-term UV irradiation, which is significant for transparent displays.

Authors:
 [1]
  1. Department of Electronic Materials Engineering, Kwangwoon University, Seoul 139-701 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22454485
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 3; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; DENSITY; DIELECTRIC MATERIALS; ELECTRIC POTENTIAL; HAFNIUM; INDIUM; IRRADIATION; LAYERS; OXYGEN; SEMICONDUCTOR MATERIALS; STABILITY; THIN FILMS; ZINC OXIDES

Citation Formats

Ha, Tae-Jun, E-mail: taejunha0604@gmail.com. Restorative effect of oxygen annealing on device performance in HfIZO thin-film transistors. United States: N. p., 2015. Web. doi:10.1063/1.4916643.
Ha, Tae-Jun, E-mail: taejunha0604@gmail.com. Restorative effect of oxygen annealing on device performance in HfIZO thin-film transistors. United States. doi:10.1063/1.4916643.
Ha, Tae-Jun, E-mail: taejunha0604@gmail.com. 2015. "Restorative effect of oxygen annealing on device performance in HfIZO thin-film transistors". United States. doi:10.1063/1.4916643.
@article{osti_22454485,
title = {Restorative effect of oxygen annealing on device performance in HfIZO thin-film transistors},
author = {Ha, Tae-Jun, E-mail: taejunha0604@gmail.com},
abstractNote = {Metal-oxide based thin-film transistors (oxide-TFTs) are very promising for use in next generation electronics such as transparent displays requiring high switching and driving performance. In this study, we demonstrate an optimized process to secure excellent device performance with a favorable shift of the threshold voltage toward 0V in amorphous hafnium-indium-zinc-oxide (a-HfIZO) TFTs by using post-treatment with oxygen annealing. This enhancement results from the improved interfacial characteristics between gate dielectric and semiconductor layers due to the reduction in the density of interfacial states related to oxygen vacancies afforded by oxygen annealing. The device statistics confirm the improvement in the device-to-device and run-to-run uniformity. We also report on the photo-induced stability in such oxide-TFTs against long-term UV irradiation, which is significant for transparent displays.},
doi = {10.1063/1.4916643},
journal = {AIP Advances},
number = 3,
volume = 5,
place = {United States},
year = 2015,
month = 3
}
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