ZNS, CDS, AND ZN1-XCDXS THIN-FILMS DEPOSITED BY THE SUCCESSIVE IONIC LAYER ADSORPTION AND REACTION PROCESS

The results of the structural, optical, and electrical characterization of ZnS, CdS, and Zn1-x CdxS films grown by the successive ionic layer adsorption and reaction process are presented. Polycrystalline cubic ZnS and hexagonal CdS films grown on glass and on indium-tin oxide covered glass have mean crystallite sizes D± = 6.5 nm and D1 = 4 nm, and Dx= 30 nm and D1 = 15 nm, respectively, perpendicular and parallel to the film. The pure cubic 3C phase is obtained from x = 0 up to x — 0.75 and the pure hexagonal 2H phase from x — 0.75 up to x = 1. Texturized heteroepitaxial films of hexagonal CdS have been grown on (111), (001), and (110) Ge, on (111), (001), and_(110) GaAs and on (111) InP substrates. Strongly texturized heteroepitaxial films of cubic ZnS have been grown on (111) InP and on (001) GaAs. Polycrystalline ZnS films consist of densely packed microcrystalline fibrous grains belonging to the transition zone T in Thornton’s structural zone model. Polycrystalline CdS films show a strong <0001> preferred orientation and have a compact columnar structure belonging to Thornton’s zone 2. ZnS and CdS films have a refractive index ranging from 2.1 to 2.25 and from 2.15 to 2.35, respectively. copyright. © 1990, The Electrochemical Society, Inc. All rights reserved.