EVAPORATED CADMIUM TELLURIDE FILMS ON STEEL FOIL SUBSTRATES

Adherent CdTe films were vacuum-evaporated on steel foil substrates he ated to between 240-degrees-C and 320-degrees-C. As-deposited films we re p-type and had a preferred (111) orientation with an average grain size of 0.6 mum. To control the electrical properties of the films, go ld or tellurium interlayers were deposited between the steel and the C dTe. A tellurium interlayer caused larger as-deposited grains than eit her the gold or bare steel. Annealing of CdTe films at 550-degrees-C i ncreased the grain size and tended to transform p-type CdTe into n-typ e. X-ray fluorescence analysis indicated that annealing had caused iro n to diffuse into the CdTe, which may have caused the type reversion.