Accession Number : AD0666403

Title :   IMPROVED II-VI CRYSTALS.

Descriptive Note : Quarterly progress summary rept. no. 4, 8 Mar 65-7 May 66,

Corporate Author : CLEVITE CORP CLEVELAND OHIO ELECTRONIC RESEARCH DIV

Personal Author(s) : Shiozawa,L. R. ; Jost,J. M.

Report Date : 01 AUG 1966

Pagination or Media Count : 36

Abstract : The program for purification of the original source material for crystal growth consists of (1) sintering under vacuum at 900C for 1 hr followed by further sintering under approx. 1 atm Ar at 1200C for an additional hour and (2) one or more vacuum fractional sublimations at 1100C. In crystal growth, dependence for high quality crystals is mainly on the open-tube, spontaneous-nucleation method at 1280C and under approx. 1 atm Ar. The advantages of epitaxial crystal growth under vacuum have not yet been completely realized. A combination of the advantages of both methods has given encouraging results. Some work on the use of small seeds has shown that conditions for promoting epitaxial growth are very critical. Mechanical and chemical polishing techniques are given in detail for the preparation of crystal specimens for microscopic examination. Crystals are being evaluated optically using noncoherent and coherent light, and electrically by photoconductivity, thermally-stimulated currents, and current saturation and oscillations. A theoretical analysis of native point defect equilibria was made.

Descriptors :   (*SEMICONDUCTORS, *CRYSTAL GROWTH), (*CADMIUM SULFIDES, PREPARATION), POWDERS, SINTERING, SUBLIMATION, NUCLEATION, EPITAXIAL GROWTH, MICROSTRUCTURE, OPTICAL PROPERTIES, ELECTRICAL PROPERTIES, PHOTOCONDUCTIVITY, THERMOELECTRICITY, CRYSTAL DEFECTS, ZINC COMPOUNDS, TELLURIDES

Subject Categories : Electrical and Electronic Equipment
      Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE