DEPOSITION AND CHARACTERIZATION OF CUINSE2

Polycrystalline CuInSe2 thin film solar cells were prepared by two methods: three-source evaporation and co-electrodeposition from a single bath. Structural and compositional characterization was carried out by X-ray diffraction, energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The evaporation technique produced chalcopyrite CIS for stoichmetric and In-rich films while the Cu-rich films exhibited only the sphalerite phase. SEM analysis shows grain sizes of 0.5-0.7 mu m for stoichmetric CIS. Electron diffraction also revealed the presence of CIS. It was found that sufficient Cu, In and Se could be co-electrodeposited from a single bath. EDS analysis showed that annealing resulted in the loss of Se. The adhesion of the film to the substrate depends critically on the current density and time of deposition.