Layer-by-layer production of CdS thin films by chemical bath deposition

In this study, the effect of the number of layers on the optical, morphological and structural features of the CdS films grown on the glass substrates using chemical bath deposition method was investigated. In the experiments, the CdS thin films with one layer, two layers and three layers were produced. According to XRD analysis, all the films exhibited a cubic structure. However, the preferred orientation of the films was affected by the number of the layers.The crystallite size decreased from 15 nm to 6 nm as the number of layers was increased. From the optical analysis of the films, it was found that the optical bandgap increased from the 2.42 eV to the 2.74 eV with increasing the number of layers. The CdS thin films with one and two layers exhibited high transmittance. From the morphological analysis of the samples, it was also revealed that the cracks and pinholes observed on the sample surfaces can be eliminated by applying the process developed in this work.