Accession Number : AD0666402

Title :   IMPROVED II-VI CRYSTALS.

Descriptive Note : Quarterly progress rept. no. 3, 8 Sep-7 Dec 65,

Corporate Author : CLEVITE CORP CLEVELAND OHIO ELECTRONIC RESEARCH DIV

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

Report Date : 06 MAR 1966

Pagination or Media Count : 38

Abstract : The results of the outgassing study CdS powder shows that most of the gases evolved during vacuum sintering are due to the presence of about 0.1 mole % hydrated CdSO4. It was found that a reduced amount of SiO2 inclusions results if epitaxial crystal growth of CdS is carried out in an unsealed tube under 1 atm Ar. X-ray fluorescence measurements show that CdSe crystals grown in this laboratory contain about 2 mole % S, which can be reduced by a Se-vapor treatment. Analysis of the solid-vapor equilibria for CdS-CdSe mixed crystals shows a variation of Kp with composition, with a pronounced minimum at 0.57 mole fraction CdS. Of extreme importance in determining the electrical properties of II-VI semiconductors are native point defects. A theoretical analysis of their equilibria shows a complex interdependence of the various defects and a necessity for experimentally determining the various equilibrium constants. A verification of the dependence of acoustic amplification properties on S pressure was made, with optimum current oscillations occurring when a minimal S pressure of about 0.2 atm at 850C is used. (Author)

Descriptors :   (*SEMICONDUCTORS, *CRYSTAL GROWTH), (*CADMIUM SULFIDES, PREPARATION), POWDERS, SINTERING, DEGASIFICATION, IMPURITIES, SULFATES, SILICON DIOXIDE, EPITAXIAL GROWTH, X RAY SPECTROSCOPY, CADMIUM SELENIDES, VAPOR PRESSURE, CRYSTAL DEFECTS, ELECTRICAL PROPERTIES, ACOUSTIC PROPERTIES, SULFUR

Subject Categories : Electrical and Electronic Equipment
      Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE