Accession Number : ADA193293

Title :   Migration and Stability of HgCdTe Lattice Defects.

Descriptive Note : Final rept. 24 Jun 85-30 Dec 87,

Corporate Author : WASHINGTON UNIV SEATTLE DEPT OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Kikuchi, Ryoichi

PDF Url : ADA193293

Report Date : 29 Feb 1988

Pagination or Media Count : 32

Abstract : Continuing from our previous work on equilibrium phase diagrams of Hg-Cd-Te systems, diffusion of Hg and Cd in HgCdTe has been studied in this project. The path probability method (PPM) of irreversible statistical mechanics is used with a point as the basic cluster. Basic formulation of diffusion: A gradient of atomic density is applied to the system and the responding atomic flux is formulated. It is noteworthy to see that chemical potential gradient appears quite naturally as the driving force, as the Onsager theory requires, rather than the atomic density gradient. Hg fast diffusion: It is made of two branches. In the vacancy mechanism branch, diffusion decreases with Hg vapor pressure, P(Hg), while it increases in the interstitial mechanism branch. Equations are derived to show these branches and curves for the diffusion coefficient are plotted. Experimentally observed activation energy is given atomic interpretation.

Descriptors :   *CRYSTAL DEFECTS, *CRYSTAL LATTICES, *MERCURY, *CADMIUM TELLURIDES, *SEMICONDUCTORS, ACTIVATION ENERGY, CLUSTERING, DIFFUSION, DIFFUSION COEFFICIENT, EQUATIONS, EQUILIBRIUM(GENERAL), FORCE(MECHANICS), FORMULATIONS, GRADIENTS, INTERSTITIAL, IRREVERSIBLE PROCESSES, PATHS, PHASE DIAGRAMS, PROBABILITY, STATISTICAL MECHANICS, VAPOR PRESSURE, SIMPLE CUBIC LATTICES

Subject Categories : Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE