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Title: Growth-temperature- and thermal-anneal-induced crystalline reorientation of aluminum on GaAs (100) grown by molecular beam epitaxy

Abstract

The authors investigated the growth of Al thin films on GaAs (100) substrates by molecular beam epitaxy. It is found that the growth at 550 degree sign C results in a texture that consists of (100)Al[010](parallel sign)(100)GaAs[011] and (100)Al[010](parallel sign)(100)GaAs[010] rotated 45 degree sign with respect to each other, while the growth at 300 degree sign C leads to a mixture phase of (100)Al[010](parallel sign)(100)GaAs[011] and (110)Al[001](parallel sign)(100)GaAs[011]. In situ annealing of the Al film grown at 300 degree sign C causes a reorientation of the crystalline from (100)Al[010](parallel sign)(100)GaAs[011] to (110)Al[001](parallel sign)(100)GaAs[011]. The grain sizes of the Al film are increased by the increased growth temperature and in situ annealing; the ratio of the exposed to the covered surface is not changed significantly by changing the growth temperature but decreased by annealing; and the small islands in between the large ones are removed by annealing. These observations are explained based on island migration and coalescence.

Authors:
; ;  [1];  [2]
  1. Institute of Materials Research and Engineering (IMRE), 3 Research Link, Singapore 117602 (Singapore)
  2. (Singapore)
Publication Date:
OSTI Identifier:
20982725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 5; Other Information: DOI: 10.1063/1.2472275; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; ANNEALING; COALESCENCE; CRYSTAL GROWTH; GALLIUM ARSENIDES; GRAIN SIZE; LAYERS; MIGRATION; MOLECULAR BEAM EPITAXY; SUBSTRATES; TEXTURE; THIN FILMS

Citation Formats

Liu, H. F., Chua, S. J., Xiang, N., and Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576. Growth-temperature- and thermal-anneal-induced crystalline reorientation of aluminum on GaAs (100) grown by molecular beam epitaxy. United States: N. p., 2007. Web. doi:10.1063/1.2472275.
Liu, H. F., Chua, S. J., Xiang, N., & Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576. Growth-temperature- and thermal-anneal-induced crystalline reorientation of aluminum on GaAs (100) grown by molecular beam epitaxy. United States. doi:10.1063/1.2472275.
Liu, H. F., Chua, S. J., Xiang, N., and Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576. Thu . "Growth-temperature- and thermal-anneal-induced crystalline reorientation of aluminum on GaAs (100) grown by molecular beam epitaxy". United States. doi:10.1063/1.2472275.
@article{osti_20982725,
title = {Growth-temperature- and thermal-anneal-induced crystalline reorientation of aluminum on GaAs (100) grown by molecular beam epitaxy},
author = {Liu, H. F. and Chua, S. J. and Xiang, N. and Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576},
abstractNote = {The authors investigated the growth of Al thin films on GaAs (100) substrates by molecular beam epitaxy. It is found that the growth at 550 degree sign C results in a texture that consists of (100)Al[010](parallel sign)(100)GaAs[011] and (100)Al[010](parallel sign)(100)GaAs[010] rotated 45 degree sign with respect to each other, while the growth at 300 degree sign C leads to a mixture phase of (100)Al[010](parallel sign)(100)GaAs[011] and (110)Al[001](parallel sign)(100)GaAs[011]. In situ annealing of the Al film grown at 300 degree sign C causes a reorientation of the crystalline from (100)Al[010](parallel sign)(100)GaAs[011] to (110)Al[001](parallel sign)(100)GaAs[011]. The grain sizes of the Al film are increased by the increased growth temperature and in situ annealing; the ratio of the exposed to the covered surface is not changed significantly by changing the growth temperature but decreased by annealing; and the small islands in between the large ones are removed by annealing. These observations are explained based on island migration and coalescence.},
doi = {10.1063/1.2472275},
journal = {Journal of Applied Physics},
number = 5,
volume = 101,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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