Accession Number:

ADA277912

Title:

Indium-Vacancy Complexes in Mercury Cadmium Telluride

Descriptive Note:

Final rept. 15 Mar 1991-30 Sep 1993

Corporate Author:

NORTH CAROLINA UNIV AT CHAPEL HILL DEPTOF PHYSICS AND ASTRONOMY

Report Date:

1993-12-20

Pagination or Media Count:

10.0

Abstract:

The goals of this research were to study specific defect configurations in Hg0.79Cd0.21TeMCT, using perturbed angular correlation PAC measurements, with emphasis on the defect consisting of vacancies trapped at the donor impurity indium secondarily, to study antisite defects and small indium precipitates. The first of these objectives was met with the identification and structural characterization of In-V sub Hg complexes. It was determined that this defect does occur under appropriate conditions reported in several publications, and that it consists of an indium impurity on a cation site, joined to a single vacancy at the 110 next nearest site. The mysterious 111 orientation of the electric field gradient EFG observed for donor- vacancy complexes in MCT and other II-VI semiconductors was shown to result from the polarization of Te atoms surrounding the indium donor. The thermodynamics of the mercury vacancy and indium-vacancy complexes were extensively characterized, resulting in good estimates of the migration energy for Hg vacancies and binding energies for vacancy-indium pairs. In-V sub Hg complexes were seen to interact with H impurities. No evidence of either antisite defects or small metal clusters was seen at doping levels up to 10exp 17Incu cm.

Subject Categories:

  • Inorganic Chemistry
  • Electrical and Electronic Equipment
  • Crystallography
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE