RESEARCH ON II-VI COMPOUND SEMICONDUCTORS.
Abstract
The separation of radioactive Ag during sublimation of CdS and CdSe was investigated and effective distribution coefficients of 0.5 and 0.15, respectively, are estimated. Trial runs in a new, travelling-hot-zone furnace show that large, seed-oriented, crystals of CdSe can be successfully grown. An analysis of precipitation mechanisms in II-VI crystals leads to the conclusion that precipitation of vacancies is required in all cases. New measurements of the refractive indices of CdS (band edge to 1.4 microns) yield long-wave optical dielectric constants of 5.16 = 0.02 for E perpendicular to C and 5.23 = 0.02 for E parallel to C. Birefringence data for CdS and CdSe are compared with the results of others. Measurements on injection luminescence in CdS diodes show that the green emission at 77K peaks at 5194A and has a halfwidth of 150A. A red band at approximately 6500A is also noted. Pulse measurements indicate a 0.2 microsec delay between the start of excitation and the onset of emission. Some measurements at 4.2K are also described. The expressions for the transport properties, applicable when more than one scattering mechanism is present, are obtained in the relaxation time approximation. The expressions are evaluated numerically and compared with several simpler approximations. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 05, 1963
- Accession Number
- AD0626537
Entities
People
- G. P. Chotkevys
- J. M. Jost
- L. R. Shiozawa
- S. S. Devlin