Effect of deposition time on physical properties of nanostructured CdS thin films grown by chemical bath deposition technique

In this study, Cadmium Sulphide (CdS) thin films are deposited at different deposition times on glass substrate by chemical bath deposition technique. The FESEM images indicated the formation of spherical nano-grains in such a way that with increasing the deposition time the grain diameters are decreased from about 100 to 60 nm. The XRD patterns showed all layers have cubic phase along (111) direction, and as the deposition time increased the crystallinity of the layers are gradually degraded, consistent with the Raman spectra. Analysis of the optical properties revealed that band gap of the films are gradually increased from 2.41 to 2.47 eV, due to defect-related band tail width variations; based on I-V measurements and PL spectra analysis.