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Title: Enhancing electron mobility in La-doped BaSnO{sub 3} thin films by thermal strain to annihilate extended defects

Abstract

We report the enhancement of room-temperature electron mobility in La-doped BaSnO{sub 3} (LBSO) thin films with thermal strain induced by high temperature nitrogen (N{sub 2}) annealing. Simple annealing under an N{sub 2} environment consistently doubled the electron mobility of the LBSO films on the SrTiO{sub 3} (STO) substrates to as high as 78 cm{sup 2} V{sup −1} s{sup −1} at a carrier concentration of 4.0 × 10{sup 20 }cm{sup −3}. This enhancement is mainly attributed to annihilation of extended defects as a consequence of compressive strain induced by the difference in the thermal expansion coefficients of LBSO and STO. Our study suggests that thermal strain can be exploited to reduce extended defects and to facilitate electron transport in transparent oxide semiconductors.

Authors:
; ;  [1]
  1. Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22590654
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 26; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABUNDANCE; ANNEALING; DOPED MATERIALS; ELECTRON MOBILITY; ELECTRON TEMPERATURE; OXIDES; SEMICONDUCTOR MATERIALS; STRAINS; STRONTIUM TITANATES; SUBSTRATES; TEMPERATURE RANGE 0273-0400 K; THERMAL EXPANSION; THIN FILMS

Citation Formats

Yu, Sangbae, Yoon, Daseob, and Son, Junwoo, E-mail: jwson@postech.ac.kr. Enhancing electron mobility in La-doped BaSnO{sub 3} thin films by thermal strain to annihilate extended defects. United States: N. p., 2016. Web. doi:10.1063/1.4954638.
Yu, Sangbae, Yoon, Daseob, & Son, Junwoo, E-mail: jwson@postech.ac.kr. Enhancing electron mobility in La-doped BaSnO{sub 3} thin films by thermal strain to annihilate extended defects. United States. doi:10.1063/1.4954638.
Yu, Sangbae, Yoon, Daseob, and Son, Junwoo, E-mail: jwson@postech.ac.kr. 2016. "Enhancing electron mobility in La-doped BaSnO{sub 3} thin films by thermal strain to annihilate extended defects". United States. doi:10.1063/1.4954638.
@article{osti_22590654,
title = {Enhancing electron mobility in La-doped BaSnO{sub 3} thin films by thermal strain to annihilate extended defects},
author = {Yu, Sangbae and Yoon, Daseob and Son, Junwoo, E-mail: jwson@postech.ac.kr},
abstractNote = {We report the enhancement of room-temperature electron mobility in La-doped BaSnO{sub 3} (LBSO) thin films with thermal strain induced by high temperature nitrogen (N{sub 2}) annealing. Simple annealing under an N{sub 2} environment consistently doubled the electron mobility of the LBSO films on the SrTiO{sub 3} (STO) substrates to as high as 78 cm{sup 2} V{sup −1} s{sup −1} at a carrier concentration of 4.0 × 10{sup 20 }cm{sup −3}. This enhancement is mainly attributed to annihilation of extended defects as a consequence of compressive strain induced by the difference in the thermal expansion coefficients of LBSO and STO. Our study suggests that thermal strain can be exploited to reduce extended defects and to facilitate electron transport in transparent oxide semiconductors.},
doi = {10.1063/1.4954638},
journal = {Applied Physics Letters},
number = 26,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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