Accession Number : AD0705486

Title :   Zn DOPING OF GaAs FILMS USING COEVAPORATION OF THE ELEMENTS,

Descriptive Note : Final rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Schmidt,W. A. ; Davey,J. E.

Report Date : 23 APR 1970

Pagination or Media Count : 21

Abstract : High optical quality polycrystalline thin GaAs films, in the thickness range from 1.0 to 10 micrometers and degenerately doped to levels of 3x 10 to the 19th power/cc, have been grown in a reproducible manner by the coevaporation techniques. An upper limit on the deposition temperature dictated by surface quality requirements results in the consistent observation of growth in the (311) or (111) textures and crystallite size significantly smaller than film thickness. This latter fact results in the mobility being limited by grain boundary scattering, the mobility being about two orders of magnitude smaller than for equivalently doped bulk GaAs. Using Zn diffusion methods on already deposited, undoped, high resistivity GaAs films results in large particle size but discontinuities in the films. Partial epitaxy on polycrystalline GaP substrates resulted in two-order-of-magnitude improvement in resistivity. These results tend to rule out use of polycrystalline GaAs films for applications where particle size of the order of film thickness is required. Epitaxial films are mandatory for equivalent bulk mobility applications. (Author)

Descriptors :   (*SEMICONDUCTING FILMS, *CRYSTAL GROWTH), (*GALLIUM ARSENIDES, DOPING), VAPOR PLATING, CRYSTAL STRUCTURE, BAND THEORY OF SOLIDS, INFRARED DETECTORS, ELECTRON DIFFRACTION, X RAY DIFFRACTION, HALL EFFECT, ZINC

Subject Categories : Crystallography
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE