Effects of temperature and r.f. power sputtering on electrical and opticalproperties of SnO2

Electrical and optical properties of SnO2, which is a photovoltaic material for solar energy conversion to electricity, have been investigated. Semi-c onducting SnO2 has been grown by r.f. sputtering. We report the influence o f process variables, such as substrate temperature and r.f. power. The film resistivity decreases with increasing temperature, but rises with increasi ng r.f. power: these can be related to crystallite size and the film orient ation respectively. From the optical measurements, we deduce a variation of band-gap energy with substrate temperature. We show that the substrate tem perature has a subsequent influence on the electrical and optical propertie s of this material. (C) 1999 Elsevier Science Ltd. All rights reserved.