Selenization process in simple spray-coated CIGS film

Abstract

The synthesis process to produce a decent thin-film CIGS layer with simple, easy, and low-cost are essential factors in CIGS solar cell technology. This study synthesized a thin layer of CIGS by a simple spray coating method and selenization process. The temperature substrate and distance between the nozzle and target are controlled to provide an even thickness coating. A one-stage selenization was carried out with temperature variations of 350, 400, and 500 °C and a three-stage selenization process as the comparison was made at 400 and 520 °C. The surface morphology, thickness, and optical properties of CIGS films were investigated as a function of the temperature of selenization. The complete CIGS solar cell prototype consists of a window, buffer, and CIGS absorber layer. The buffer layer used is ZnS deposited by the chemical bath deposition method, while the window layer of ZnO is deposited by the spin coating method. The SEM characterization showed a thinner layer of CIGS as temperature, and the heating rate of the selenization increased. The increasing selenization temperature also affects the Selenium deficiency that causes low Ga/(In + Ga) content and increases the bandgap energy. By the grain growth model and the kinetic study yielded estimated activation energy, which one step selenization of the process is higher than the three steps of the selenization process. PV82QJC8Y.