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Title: Correlation among Channeling, Morphological and Micro-structural Properties in Epitaxial CeO2 Films

Abstract

We report an evidence of a critical thickness at ~ 64 nm in epitaxial CeO2 films grown at 750 0C on YSZ substrates by dc magnetron sputtering where optimum ion channeling can be correlated with overall strain relaxation and film surface roughness. The occurrence of saturation in ion channeling yield, enhancement in the average surface roughness and relaxation in c-axis strain is clearly evident in thicker films beyond the critical thickness. Despite excellent surface smoothness and overall epitaxial growth, CeO2 films grown at 650 0C did not show optimum ion channeling properties due to high misfit dislocation and defect density. These results are discussed from a viewpoint of the need for such an optimum thickness to develop multilayers with smooth interfaces with relative overall lattice relaxation.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
881091
Report Number(s):
PNNL-SA-47505
6499; KP1704020; TRN: US200612%%700
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Electrochemical and Solid-State Letters, 9(5):J17-J20; Journal Volume: 9; Journal Issue: 5
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CERIUM OXIDES; DISLOCATIONS; ION CHANNELING; ROUGHNESS; STRAINS; THICKNESS; EPITAXY; STRESS RELAXATION; MICROSTRUCTURE; Environmental Molecular Sciences Laboratory

Citation Formats

Saraf, Laxmikant V., McCready, David E., Shutthanandan, V., Wang, Chong M., Engelhard, Mark H., and Thevuthasan, Suntharampillai. Correlation among Channeling, Morphological and Micro-structural Properties in Epitaxial CeO2 Films. United States: N. p., 2006. Web. doi:10.1149/1.2186029.
Saraf, Laxmikant V., McCready, David E., Shutthanandan, V., Wang, Chong M., Engelhard, Mark H., & Thevuthasan, Suntharampillai. Correlation among Channeling, Morphological and Micro-structural Properties in Epitaxial CeO2 Films. United States. doi:10.1149/1.2186029.
Saraf, Laxmikant V., McCready, David E., Shutthanandan, V., Wang, Chong M., Engelhard, Mark H., and Thevuthasan, Suntharampillai. Mon . "Correlation among Channeling, Morphological and Micro-structural Properties in Epitaxial CeO2 Films". United States. doi:10.1149/1.2186029.
@article{osti_881091,
title = {Correlation among Channeling, Morphological and Micro-structural Properties in Epitaxial CeO2 Films},
author = {Saraf, Laxmikant V. and McCready, David E. and Shutthanandan, V. and Wang, Chong M. and Engelhard, Mark H. and Thevuthasan, Suntharampillai},
abstractNote = {We report an evidence of a critical thickness at ~ 64 nm in epitaxial CeO2 films grown at 750 0C on YSZ substrates by dc magnetron sputtering where optimum ion channeling can be correlated with overall strain relaxation and film surface roughness. The occurrence of saturation in ion channeling yield, enhancement in the average surface roughness and relaxation in c-axis strain is clearly evident in thicker films beyond the critical thickness. Despite excellent surface smoothness and overall epitaxial growth, CeO2 films grown at 650 0C did not show optimum ion channeling properties due to high misfit dislocation and defect density. These results are discussed from a viewpoint of the need for such an optimum thickness to develop multilayers with smooth interfaces with relative overall lattice relaxation.},
doi = {10.1149/1.2186029},
journal = {Electrochemical and Solid-State Letters, 9(5):J17-J20},
number = 5,
volume = 9,
place = {United States},
year = {Mon Mar 20 00:00:00 EST 2006},
month = {Mon Mar 20 00:00:00 EST 2006}
}
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