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Title: Lattice thermal expansion for normal tetrahedral compound semiconductors

Abstract

The cubic root of the deviation of the lattice thermal expansion from that of the expected value of diamond for group IV semiconductors, binary compounds of III-V and II-VI, as well as several ternary compounds from groups I-III-VI{sub 2}, II-IV-V{sub 2} and I-IV{sub 2}V{sub 3} semiconductors versus their bonding length are given straight lines. Their slopes were found to be 0.0256, 0.0210, 0.0170, 0.0259, 0.0196, and 0.02840 for the groups above, respectively. Depending on the valence electrons of the elements forming these groups, a formula was found to correlate all the values of the slopes mentioned above to that of group IV. This new formula which depends on the melting point and the bonding length as well as the number of valence electrons for the elements forming the compounds, will gives best calculated values for lattice thermal expansion for all compounds forming the groups mentioned above. An empirical relation is also found between the mean ionicity of the compounds forming the groups and their slopes mentioned above and that gave the mean ionicity for the compound CuGe{sub 2}P{sub 3} in the range of 0.442.

Authors:
 [1]
  1. Department of Physics, College of Science, University of Salahaddin, Arbil, Iraqi Kurdistan (Iraq). E-mail: dr_m_s_omar@yahoo.com
Publication Date:
OSTI Identifier:
21000593
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 42; Journal Issue: 2; Other Information: DOI: 10.1016/j.materresbull.2006.05.031; PII: S0025-5408(06)00240-6; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; BONDING; DIAMONDS; ELECTRONS; MELTING POINTS; SEMICONDUCTOR MATERIALS; THERMAL EXPANSION; VALENCE

Citation Formats

Omar, M.S. Lattice thermal expansion for normal tetrahedral compound semiconductors. United States: N. p., 2007. Web. doi:10.1016/j.materresbull.2006.05.031.
Omar, M.S. Lattice thermal expansion for normal tetrahedral compound semiconductors. United States. doi:10.1016/j.materresbull.2006.05.031.
Omar, M.S. Thu . "Lattice thermal expansion for normal tetrahedral compound semiconductors". United States. doi:10.1016/j.materresbull.2006.05.031.
@article{osti_21000593,
title = {Lattice thermal expansion for normal tetrahedral compound semiconductors},
author = {Omar, M.S.},
abstractNote = {The cubic root of the deviation of the lattice thermal expansion from that of the expected value of diamond for group IV semiconductors, binary compounds of III-V and II-VI, as well as several ternary compounds from groups I-III-VI{sub 2}, II-IV-V{sub 2} and I-IV{sub 2}V{sub 3} semiconductors versus their bonding length are given straight lines. Their slopes were found to be 0.0256, 0.0210, 0.0170, 0.0259, 0.0196, and 0.02840 for the groups above, respectively. Depending on the valence electrons of the elements forming these groups, a formula was found to correlate all the values of the slopes mentioned above to that of group IV. This new formula which depends on the melting point and the bonding length as well as the number of valence electrons for the elements forming the compounds, will gives best calculated values for lattice thermal expansion for all compounds forming the groups mentioned above. An empirical relation is also found between the mean ionicity of the compounds forming the groups and their slopes mentioned above and that gave the mean ionicity for the compound CuGe{sub 2}P{sub 3} in the range of 0.442.},
doi = {10.1016/j.materresbull.2006.05.031},
journal = {Materials Research Bulletin},
number = 2,
volume = 42,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
  • A general empirical formula was found for calculating lattice thermal expansion for compounds having their properties extended for compound groups having different mean ionicity as well as more than one type of cation atoms with that of different numbers of them such as I{sub 2}-IV-VI{sub 3} and I{sub 3}-V-VI{sub 4}. The difference in the valence electrons for cations and anions in the compound was used to correlate the deviations caused by the compound ionicity. The ionicity effects, which are due to their different numbers for their types, were also added to the correlation equation. In general, the lattice thermal expansionmore » for a compound semiconductor can be calculated from a relation containing melting point, mean atomic distance and number of valence electrons for the atoms forming the compound. The mean ionicity for the group compounds forming I{sub 2}-IV-VI{sub 3} was found to be 0.323 and 0.785 for the ternary group compounds of I{sub 3}-V-VI{sub 4}.« less
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