CdS films from two different low cost techniques for solar cell applications – a comparative study

Abstract

CdS films with good structural and optical properties were fabricated by employing a simple and inexpensive spray pyrolysis technique using a perfume atomizer. The films were deposited at a relatively low substrate temperature (280°C) compared with conventional spray pyrolysis technique. The microstructure, surface morphology and optical properties of the sprayed CdS films prepared from starting solutions having different S/Cd ratios (1 : 1, 3 : 1and 5 : 1) were investigated and compared with that of the chemical bath deposited films. It was observed that, for the sprayed CdS films, the preferred orientation changes from (002) plane to (101) plane when S/Cd ratio in the starting solution increases, whereas in the case of their chemical bath deposited counterparts only the degree of preferred orientation increases with the increase in S/Cd ratio. The sprayed CdS films showed good visible transmittance (>85%) and wide optical band gap (2·42 eV) suitable for solar cell applications.