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Title: Insights on semiconductor-metal transition in indium-doped zinc oxide from x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and x-ray diffraction

Abstract

ZnO thin films doped with various amounts of In impurities were prepared by magnetron sputtering at a substrate temperature of 150°C. The shift in optical bandgap of the In-doped ZnO films is studied as a function of carrier concentration. Nominally doped ZnO films exhibit an increase in the measured optical band gap known as the Burstein-Moss effect. Dominant band gap narrowing is observed with increased doping. XPS and TOFSIMS analyses confirm that In is incorporated in the ZnO material. The In 3d peaks show that no metallic In is present as a result of heavy doping. The XRD phase analysis shows a preferential c-axis growth but a shift of the ZnO (002) peak to lower 2-theta values with increasing FWHM as the carrier concentration increases indicates the decline in the quality of crystallinity. An elongation of the c lattice constant is also observed and is likely to be caused by intersitital In as the amount of In dopants increases. The incorporation of In induces a semiconductor-metal transition between the carrier concentrations of 3.58 – 5.61×10{sup 19} cm{sup −3} and structural changes in the ZnO host material.

Authors:
;  [1]; ;  [2];  [3]
  1. Physics Programme, School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia)
  2. Nano-optoelectronics Research Laboratory, Universiti Sains Malaysia, 11800 Penang (Malaysia)
  3. School of Materials and Mineral Resources Eng., Universiti Sains Malaysia, 14300 Nibong Tebal (Malaysia)
Publication Date:
OSTI Identifier:
22608594
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1733; Journal Issue: 1; Conference: IC-NET 2015: International conference on nano-electronic technology devices and materials 2015, Selangor (Malaysia), 27 Feb - 2 Mar 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARRIERS; CONCENTRATION RATIO; DOPED MATERIALS; ELONGATION; IMPURITIES; INDIUM ADDITIONS; LATTICE PARAMETERS; MAGNETRONS; MASS; MASS SPECTROSCOPY; PHASE STUDIES; SEMICONDUCTOR MATERIALS; SPUTTERING; SUBSTRATES; THIN FILMS; TIME-OF-FLIGHT METHOD; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY; ZINC OXIDES

Citation Formats

Saw, K. G., E-mail: kgsaw@usm.my, Aznan, N. M., E-mail: nanieaz1004@gmail.com, Yam, F. K., E-mail: yamfk@yahoo.com, Ng, S. S., E-mail: shashiong@usm.my, and Pung, S. Y., E-mail: sypung@usm.my. Insights on semiconductor-metal transition in indium-doped zinc oxide from x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and x-ray diffraction. United States: N. p., 2016. Web. doi:10.1063/1.4948851.
Saw, K. G., E-mail: kgsaw@usm.my, Aznan, N. M., E-mail: nanieaz1004@gmail.com, Yam, F. K., E-mail: yamfk@yahoo.com, Ng, S. S., E-mail: shashiong@usm.my, & Pung, S. Y., E-mail: sypung@usm.my. Insights on semiconductor-metal transition in indium-doped zinc oxide from x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and x-ray diffraction. United States. doi:10.1063/1.4948851.
Saw, K. G., E-mail: kgsaw@usm.my, Aznan, N. M., E-mail: nanieaz1004@gmail.com, Yam, F. K., E-mail: yamfk@yahoo.com, Ng, S. S., E-mail: shashiong@usm.my, and Pung, S. Y., E-mail: sypung@usm.my. 2016. "Insights on semiconductor-metal transition in indium-doped zinc oxide from x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and x-ray diffraction". United States. doi:10.1063/1.4948851.
@article{osti_22608594,
title = {Insights on semiconductor-metal transition in indium-doped zinc oxide from x-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry and x-ray diffraction},
author = {Saw, K. G., E-mail: kgsaw@usm.my and Aznan, N. M., E-mail: nanieaz1004@gmail.com and Yam, F. K., E-mail: yamfk@yahoo.com and Ng, S. S., E-mail: shashiong@usm.my and Pung, S. Y., E-mail: sypung@usm.my},
abstractNote = {ZnO thin films doped with various amounts of In impurities were prepared by magnetron sputtering at a substrate temperature of 150°C. The shift in optical bandgap of the In-doped ZnO films is studied as a function of carrier concentration. Nominally doped ZnO films exhibit an increase in the measured optical band gap known as the Burstein-Moss effect. Dominant band gap narrowing is observed with increased doping. XPS and TOFSIMS analyses confirm that In is incorporated in the ZnO material. The In 3d peaks show that no metallic In is present as a result of heavy doping. The XRD phase analysis shows a preferential c-axis growth but a shift of the ZnO (002) peak to lower 2-theta values with increasing FWHM as the carrier concentration increases indicates the decline in the quality of crystallinity. An elongation of the c lattice constant is also observed and is likely to be caused by intersitital In as the amount of In dopants increases. The incorporation of In induces a semiconductor-metal transition between the carrier concentrations of 3.58 – 5.61×10{sup 19} cm{sup −3} and structural changes in the ZnO host material.},
doi = {10.1063/1.4948851},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1733,
place = {United States},
year = 2016,
month = 7
}
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