Nanocrystalline TiO2-doped films, with various volume fractions of CdTe, were prepared by radio-frequency magnetron sputtering from a composite TiO2:CdTe target. The structural and electrical properties of the films were analyzed as a function of their Cd concentration. It was found that thermally treated films were Cd-rich, stress free and had lower resistivities. Field-dependent current measurements showed that nanocrystalline films, upon heat-treatment at 250 to 300C, exhibited an unusual current peak under certain conditions of field and temperature. The current peak was associated with the presence of Cd-related defects in the CdTe lattice. The threshold temperature for the formation of Cd-related defects shifted to lower values in Cd-deficient films.

Role of Cadmium-Related Defects on the Structural and Electrical Properties of Nanocrystalline CdTe:TiO2 Sputtered Films. S.N.Sharma, S.Kohli, A.C.Rastogi: Current Applied Physics, 2003, 3[2-3], 263-7