Structural, optical and electrical properties of SnO2:F and CdS airless sprayed layers

Abstract

We have investigated some properties of SnO2:F and CdS airless spray layers in order to determine the best preparation conditions for the realization of CdS based photocells. The layers are made by means of single spraying of aqueous solutions containing cadmium chloride or nitrate and thiourea on heated glass substrates at 420°C. The deposition technique employs an airless spray gun which allows the use of a more concentrated solution as well as a lower deposition temperature than used in pyrolysis. A conductive tin oxide film was used for making the negative contact of the solar cells. The transmittance and reflectance measurements showed that the layers of cadmium sulfide made from the chloride process are transparent at wavelengths λ > 510 nm. However, the structural properties of CdS showed inhomogeneous layers. CdS made by the nitrate process has been also analyzed. The conversion efficiency of CdSCuxS solar cells attains 3.7% for nonoptimized CdS layers, that could be improved. © 1987.