Investigation of some physical properties of ZnO, CdS, PbS thin films produced by chemical bath deposition method for solar cells

As the energy need of humanity increases in today's world, traditional energy production technologies are replaced by renewable energy sources. Since solar energy is an unlimited and clean energy source, it is more popular among renewable energy sources than ever before. Solar cells are used to convert solar rays which passing the atmosphere and reach earth into electrical energy. The main problem that photovoltaic applications production technologies must overcome is that the produced electrical energy could be produced with high efficiency and low costs. For this purpose, in this thesis, semiconductor thin films, which are the fundamentals of solar cells, have been deposited on glass substrate surfaces with the Chemical Bath Deposition (CBD) method. Because of this method is low cost, being applicable to large surfaces, being a repeatable and easy production technique. Zinc oxide (ZnO), lead sulfide (PbS) and cadmium sulfide (CdS) thin films, which are among the semiconductor thin films that have been used in various gas and moisture sensor applications as well as solar cells, have been preferred. While producing ZnO, the optical, structural and morphological effects of the agent (ligand) chemicals, bath temperature and the stirring rate of the solution on the films were examined. While the PbS and CdS was produced, the optical, structural and morphological effects of the thiourea on the film were analyzed by adding certain amounts to the final solution at specific time intervals. These effects were examined with UV-vis, FTIR, XRD and SEM, respectively. As a result of the study, it was seen that ZnO, PbS and CdS thin films adhere well to the surfaces of glass substrate and compact and homogeneous films could be obtained. Optimum conditions of film production were determined for ZnO thin films, PbS and CdS thin films were produced without cracks and pinholes.