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Title: Growth of ZnO Thin Films on C-Plane AL 2O 3 by Molecular Beam Epitaxy Using Ozone as an Oxygen Source

Abstract

The growth of c-axis oriented ZnO thin films on c-plane Al2O3 via molecular beam epitaxy (MBE) using dilute ozone (O3) as an oxygen source was investigated. Four-circle X-ray diffraction (XRD) indicates that films grown at 350 8C are epitaxial with respect to the substrate, but with a broad in-plane and out-of-plane mosaic. The films were highly conductive and n-type. Epitaxial film growth required relatively high Zn flux and O3/O2 pressure. The growth rate decreased rapidly as growth temperature was increased above 350 8C. The drop in growth rate with temperature reflects the low sticking coefficient of Zn at moderately high temperatures and limited ozone flux for the oxidation of the Zn metal. Characterization of the films included atomic force microscopy (AFM), X-ray diffraction, photoluminescence, and Hall measurements. These results show that molecular beam epitaxy of ZnO using ozone is rate limited by the ozone flux for growth temperatures above 350 8C.

Authors:
 [1];  [2];  [2];  [2];  [3]
  1. University of Florida, Gainesville
  2. University of Florida
  3. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
966716
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Surface Science; Journal Volume: 252; Journal Issue: 20
Country of Publication:
United States
Language:
English
Subject:
Thin Films; c-plane

Citation Formats

Heo, YW, Ip, K., Pearton, S. J., Norton, David P., and Budai, John D. Growth of ZnO Thin Films on C-Plane AL2O3 by Molecular Beam Epitaxy Using Ozone as an Oxygen Source. United States: N. p., 2006. Web. doi:10.1016/j.apsusc.2005.08.094.
Heo, YW, Ip, K., Pearton, S. J., Norton, David P., & Budai, John D. Growth of ZnO Thin Films on C-Plane AL2O3 by Molecular Beam Epitaxy Using Ozone as an Oxygen Source. United States. doi:10.1016/j.apsusc.2005.08.094.
Heo, YW, Ip, K., Pearton, S. J., Norton, David P., and Budai, John D. Sun . "Growth of ZnO Thin Films on C-Plane AL2O3 by Molecular Beam Epitaxy Using Ozone as an Oxygen Source". United States. doi:10.1016/j.apsusc.2005.08.094.
@article{osti_966716,
title = {Growth of ZnO Thin Films on C-Plane AL2O3 by Molecular Beam Epitaxy Using Ozone as an Oxygen Source},
author = {Heo, YW and Ip, K. and Pearton, S. J. and Norton, David P. and Budai, John D},
abstractNote = {The growth of c-axis oriented ZnO thin films on c-plane Al2O3 via molecular beam epitaxy (MBE) using dilute ozone (O3) as an oxygen source was investigated. Four-circle X-ray diffraction (XRD) indicates that films grown at 350 8C are epitaxial with respect to the substrate, but with a broad in-plane and out-of-plane mosaic. The films were highly conductive and n-type. Epitaxial film growth required relatively high Zn flux and O3/O2 pressure. The growth rate decreased rapidly as growth temperature was increased above 350 8C. The drop in growth rate with temperature reflects the low sticking coefficient of Zn at moderately high temperatures and limited ozone flux for the oxidation of the Zn metal. Characterization of the films included atomic force microscopy (AFM), X-ray diffraction, photoluminescence, and Hall measurements. These results show that molecular beam epitaxy of ZnO using ozone is rate limited by the ozone flux for growth temperatures above 350 8C.},
doi = {10.1016/j.apsusc.2005.08.094},
journal = {Applied Surface Science},
number = 20,
volume = 252,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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