Preparation and characterization of ZnS thin films by the chemical bath deposition method

ZnS thin films prepared on quartz substrates by the chemical bath deposition (CBD) method with three type temperature profile processes have been investigated by X-ray diffraction, scanning electron microscope, energy dispersive X-ray analysis and light transmission. One is a 1-step growth process, and the other is 2-steps growth and self-catalyst growth processes. The surface morphology of CBD-ZnS thin films prepared by the CBD method with the self-catalyst growth process is flat and smooth compared with that prepared by the 1-step and 2-steps growth processes. The self-catalyst growth process in order to prepare the particles of ZnS as initial nucleus layer was useful for improvement in crystallinity of ZnS thin films prepared by CBD. ZnS thin films prepared by CBD method with self-catalyst growth process can be expected for improvement in the conversion efficiency of Cu(InGa)Se2-based thin film solar cells by using it for the buffer layer.

► ZnS thin films were prepared by chemical bath deposition (CBD) method.
► The crystallization of CBD-ZnS films was further improved.
► The crystallinity of CBD-ZnS thin films is dependent on the zinc source material.
► Self-catalyst growth process is useful for the growth of thin films by CBD method.
► It is expected to improve the conversion efficiency of CuIn1-xGaxSe2 solar cells.