PROPERTIES OF 2-PHASE CADMIUM STANNATE THIN-FILMS

Thin films of cadmium stannate were prepared from a Cd2SnO4 target by r.f. sputtering. Optical and electrical properties were studied as functions of film thickness and related to changes in composition and structure; in particular, the presence of both amorphous and crystalline phases within the same film was demonstrated for the first time. The surface composition of the films, in contrast to the bulk composition, was shown to be significantly affected by heat treatment, with clear implications for the use of cadmium stannate as a transparent conductor in electronic devices. It is concluded that failure to control adequately parameters such as deposition temperature can lead to non-uniformity of structure and properties within a single run and variability from one run to another. © 1990.