Preparation of Optical Quality ZnCdTe Thin Films by Vacuum Evaporation.

A procedure to make optical quality thin films of ZnxCd1-xTe by use of vacuum evaporation of the ternary compound has been developed. The starting point was the preparation of the compound that was then used as the source in a simple vacuum evaporation system. The characteristics of a film containing 85% ZnTe (x = 0.85) are presented. Electron microscope, atomic force microscope, x-ray and optical spectral measurements were made. The index of refraction was determined at room temperature from transmittance measurements in the range of from 580 to 800 nm and was found to agree within 1% with values found by others for single crystals. We did this by assuming a Sellmeier equation and a known index of refraction at infinite wavelength. The calculation also yielded the roughness of the film.