Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom

Duenweg, B; Landau, D P

Title: Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom

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Abstract

A statistical-mechanical model of binary semiconductor alloys, consisting of a distortable diamond lattice whose sites may be occupied by A atoms, B atoms, or vacancies, is studied by constant pressure Monte Carlo simulations. The model allows for atomic displacements governed by the Keating valence force field. The interplay between the chemical and translational degrees of freedom shows up in the form of the unmixing phase diagram of a system whose parameters were chosen in an attempt to mimic a Si-Ge alloy. The critical behavior of the unmixing transition is studied by a multi histogram data analysis and found to be Mean Field-like. Vegard`s law is verified but the Keating potential leads to a negative coefficient of thermal expansion.

Authors:

Duenweg, B; Landau, D P ^[1]

Univ. of Georgia, Athens, GA (United States). Center for Simulational Physics

Publication Date:: Sat Dec 31 00:00:00 EST 1994

OSTI Identifier:: 72410

Report Number(s):: CONF-9310224-
ISBN 0-87339-249-3; TRN: IM9530%%22

Resource Type:: Conference

Resource Relation:: Conference: Materials Week `93, Pittsburgh, PA (United States), 17-21 Oct 1993; Other Information: PBD: 1994; Related Information: Is Part Of Alloy modeling and design; Stocks, G.M. [ed.] [Oak Ridge National Lab., Oak Ridge, TN (United States). Metals and Ceramics Div.]; Turchi, P.E.A. [ed.] [Lawrence Livermore National Lab., Livermore, CA (United States)]; PB: 334 p.

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; SILICON ALLOYS; PHASE DIAGRAMS; PHYSICAL PROPERTIES; GERMANIUM ALLOYS; MONTE CARLO METHOD; COMPUTERIZED SIMULATION; MATHEMATICAL MODELS; STATISTICAL MECHANICS; VEGARD LAW; ATOMIC DISPLACEMENTS; TEMPERATURE DEPENDENCE; ALGORITHMS; POTENTIALS; THERMAL EXPANSION

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                    Duenweg, B, and Landau, D P. Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom.  United States: N. p., 1994. 
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                    Duenweg, B, & Landau, D P. Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom.  United States.

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                    Duenweg, B, and Landau, D P. 1994.  
        "Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom".  United States.

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@article{osti_72410,

  title        = {Monte Carlo studies of unmixing in semiconductor alloys: Effects of elastic degrees of freedom},

  author       = {Duenweg, B and Landau, D P},

  abstractNote = {A statistical-mechanical model of binary semiconductor alloys, consisting of a distortable diamond lattice whose sites may be occupied by A atoms, B atoms, or vacancies, is studied by constant pressure Monte Carlo simulations. The model allows for atomic displacements governed by the Keating valence force field. The interplay between the chemical and translational degrees of freedom shows up in the form of the unmixing phase diagram of a system whose parameters were chosen in an attempt to mimic a Si-Ge alloy. The critical behavior of the unmixing transition is studied by a multi histogram data analysis and found to be Mean Field-like. Vegard`s law is verified but the Keating potential leads to a negative coefficient of thermal expansion.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/72410},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sat Dec 31 00:00:00 EST 1994},

  month        = {Sat Dec 31 00:00:00 EST 1994}

}

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