STRUCTURAL AND OPTICAL-PROPERTIES OF CDSEXTE1-X THIN-FILMS GROWN BY ELECTRON-BEAM EVAPORATION

CdSexTex-1 (0 less than or equal to x less than or equal to 1) ternary thin films have been deposited on glass substrates at room temperatur e by electron beam evaporation, using the source materials prepared in our laboratory by direct reaction of high purity elemental Cd(99.9999 %), Se(99.999%) and Te(99.999%). These alloy films independent of comp osition, are polycrystalline, single phase (zinc blende structure) wit h strong preferential orientation of the crystallites (30-50 nm size) along (111) direction. Linear variation of lattice constant with compo sition (x) is observed. Absorption measurements show quadratic variati on of bandgap with composition (x). Refractive indices, determined fro m transmission spectra, are in the range 2.43-2.52 depending upon the composition of the films.