Experiments on the microstructure of evaporated CuInS2 thin films

The morphology and microstructure of evaporated CuInS2 films is investigated with the emphasis on the effect of stoichiometry deviations. The compositions of In-rich and Cu-rich films obey the relations In2S3-CuInS2 and CuS-CuInS2 in the ternary phase diagram, respectively. In-rich films exhibit a platelet-like grain structure. This morphology can be explained by the formation of twin dislocations. Cu-rich films show a textured morphology with grain sizes in the range of 1-4 mu m.