CHARACTERIZATION OF CDTE-IN CO-SPUTTERED FILMS

CdTe-In films were grown on Coming glass substrates by means of the ra dio frequency sputtering deposition technique. The ternary alloys were produced by co-sputtering from a target containing CdTe and In. The I n doping effect in CdTe is studied and the different kinds of compound materials that are formed when CdTe and In are mixed. Several kinds o f materials are obtained depending on In concentration in the films an d the substrate temperature during the deposition. The electrical and structural properties of the obtained materials are reported. The comp osition measurements by Auger electron spectroscopy show that In conte nt in the films runs from 8 to 58 at.%, depending on the area fraction covered by the In piece glued onto the CdTe target. Low In concentrat ion in the films grown at room temperature produces a low level of In doping in the CdTe cubic lattice. At higher In concentrations a crysta lline structural transition to the CdTe hexagonal phase is observed in the films and then the formation of Cd-Te-In ternary structure is obt ained. Ternary compound thin films of materials with composition on th e pseudo-binary system CdTe-In2Te3 can be prepared by this growth tech nique at high substrate temperatures. (C) 1997 Elsevier Science Ltd.