Accession Number : ADA335799

Title :   Theory of Indium Thallium Phosphide

Descriptive Note : Final rept.

Corporate Author : SRI INTERNATIONAL MENLO PARK CA

Personal Author(s) : Krishnamurthy, S.

PDF Url : ADA335799

Report Date : 15 JAN 1998

Pagination or Media Count : 52

Abstract : We have used a combination of first principles and empirical band structures to study various properties of new classes of IR materials, the III-V alloys In(1-x)TlxQ, where Q=P, As, or Sb: temperature variation of the band gap, absorption coefficient, minority carrier lifetimes, thermodynamic phase diagram, low-field electron and hole mobilities, native point defect (such as vacancies and antisites) concentrations, parameters needed for modeling MBE growth. We found that, in the case of the LWIR InTlP alloy, the band gap increases with temperature, growth requires very high P vapor pressures, the electron mobility and absorption coefficients are comparable to those of LWIR HgCdTe, and the minority carrier lifetimes are about one-third of that in HgCdTe. The overall conclusion is that InTlP has serious growth-related problems that can be overcome only with novel nonequilibrium growth methods or high pressure LPE growth. InTlAs is a more promising candidate to be grown because the Tl concentration needed to attain an LWIR response is lower and the vapor pressure needed to grow it is also much lower. Moreover its Auger lifetime is predicted to be about a factor of 10 larger than that of HgCdTe.

Descriptors :   *INDIUM PHOSPHIDES, *THALLIUM COMPOUNDS, TEMPERATURE, THERMODYNAMICS, CHARGE CARRIERS, INDIUM ALLOYS, EPITAXIAL GROWTH, HIGH PRESSURE, ALLOYS, POINT DEFECTS, VARIATIONS, ELECTRONS, PHOSPHIDES, GROUP III COMPOUNDS, GROUP IV COMPOUNDS, GROUP V COMPOUNDS, NONEQUILIBRIUM FLOW, VAPOR PRESSURE, PHOSPHORUS, ANTIMONY, ARSENIC, AUGERS, MERCURY CADMIUM TELLURIDES, ABSORPTION COEFFICIENTS, FIELD CONDITIONS, PHASE DIAGRAMS, ELECTRON MOBILITY, MOLECULAR BEAM EPITAXY.

Subject Categories : Inorganic Chemistry
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE