Influence of annealing conditions on the structure and compositions of electrodeposited CuInSe2 films

The synthesis of highly crystalline CuInSe2 films through one-step electrodeposited CuInSe2 precursors followed by annealing under selenium vapor is a promising approach for fabricating low cost, high efficiency solar cells. In this study, the phase structure and crystallinity of annealed samples prepared by electrodeposition were investigated using X-ray diffraction, Raman spectroscopy and scanning electron microscopy. A detailed Raman scattering analysis showed that the formation of the Cu–Se compound and crystalline quality of the CuInSe2 can be controlled through varying the annealing temperature and annealing profile. Both the enhancement of the annealing temperature and the increase of the heating rate can lead to a significant decrease in Cu–Se compound and a remarkable increase in the grain size of the CuInSe2.