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Title: Transition in electron scattering mechanism in atomic layer deposited Nb:TiO{sub 2} thin films

Abstract

We characterized transport and optical properties of atomic layer deposited Nb:TiO{sub 2} thin films on glass substrates. These promising transparent conducting oxide (TCO) materials show minimum resistivity of 1.0 × 10{sup −3 }Ω cm at 300 K and high transmittance in the visible range. Low-temperature (2–300 K) Hall measurements and the Drude fitting of the Vis-NIR optical spectra indicate a transition in the scattering mechanism from grain boundary scattering to intra-grain scattering with increasing Nb content, thus underlining enhancement of the grain size in the low doping regime as the key for further improved TCO properties.

Authors:
;  [1]; ;  [2];  [3];  [3]
  1. Department of Chemistry, Aalto University, FI-00076 Aalto (Finland)
  2. Department of Chemistry, The University of Tokyo, Tokyo 113-0033 (Japan)
  3. (Japan)
Publication Date:
OSTI Identifier:
22415189
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; 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; DEPOSITION; GRAIN BOUNDARIES; GRAIN SIZE; HALL EFFECT; LAYERS; NIOBIUM; OPTICAL PROPERTIES; SCATTERING; SUBSTRATES; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; THIN FILMS; TITANIUM OXIDES

Citation Formats

Niemelä, Janne-Petteri, Karppinen, Maarit, E-mail: maarit.karppinen@aalto.fi, Hirose, Yasushi, Hasegawa, Tetsuya, Kanagawa Academy of Science and Technology, Kawasaki 213-0012, and CREST, Japan Science and Technology Agency, Tokyo 113-0033. Transition in electron scattering mechanism in atomic layer deposited Nb:TiO{sub 2} thin films. United States: N. p., 2015. Web. doi:10.1063/1.4906865.
Niemelä, Janne-Petteri, Karppinen, Maarit, E-mail: maarit.karppinen@aalto.fi, Hirose, Yasushi, Hasegawa, Tetsuya, Kanagawa Academy of Science and Technology, Kawasaki 213-0012, & CREST, Japan Science and Technology Agency, Tokyo 113-0033. Transition in electron scattering mechanism in atomic layer deposited Nb:TiO{sub 2} thin films. United States. doi:10.1063/1.4906865.
Niemelä, Janne-Petteri, Karppinen, Maarit, E-mail: maarit.karppinen@aalto.fi, Hirose, Yasushi, Hasegawa, Tetsuya, Kanagawa Academy of Science and Technology, Kawasaki 213-0012, and CREST, Japan Science and Technology Agency, Tokyo 113-0033. Mon . "Transition in electron scattering mechanism in atomic layer deposited Nb:TiO{sub 2} thin films". United States. doi:10.1063/1.4906865.
@article{osti_22415189,
title = {Transition in electron scattering mechanism in atomic layer deposited Nb:TiO{sub 2} thin films},
author = {Niemelä, Janne-Petteri and Karppinen, Maarit, E-mail: maarit.karppinen@aalto.fi and Hirose, Yasushi and Hasegawa, Tetsuya and Kanagawa Academy of Science and Technology, Kawasaki 213-0012 and CREST, Japan Science and Technology Agency, Tokyo 113-0033},
abstractNote = {We characterized transport and optical properties of atomic layer deposited Nb:TiO{sub 2} thin films on glass substrates. These promising transparent conducting oxide (TCO) materials show minimum resistivity of 1.0 × 10{sup −3 }Ω cm at 300 K and high transmittance in the visible range. Low-temperature (2–300 K) Hall measurements and the Drude fitting of the Vis-NIR optical spectra indicate a transition in the scattering mechanism from grain boundary scattering to intra-grain scattering with increasing Nb content, thus underlining enhancement of the grain size in the low doping regime as the key for further improved TCO properties.},
doi = {10.1063/1.4906865},
journal = {Applied Physics Letters},
number = 4,
volume = 106,
place = {United States},
year = {Mon Jan 26 00:00:00 EST 2015},
month = {Mon Jan 26 00:00:00 EST 2015}
}
  • We have fabricated high-quality thin films of the transparent conducting anatase Nb:TiO{sub 2} on glass substrates through atomic layer deposition, and a subsequent reductive heat treatment of the as-deposited amorphous films. Hall-effect measurements and Drude-fitting of the Vis-NIR spectra indicate that for lightly doped films deposited at temperatures around 170 °C, grain boundary scattering becomes negligible and the mobility is predominately limited by phonon-electron scattering inherent to the anatase lattice and by impurities. Simultaneously, such lighter doping leads to reduced plasma absorption, thereby improving material's performance as a transparent conductor.
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