Impact of annealing on the investigation of In3Se2/Cu2Se/In3Se2 sandwich structure prepared by thermal evaporation technique for solar cell applications

The present study investigates the effect of annealing on In3Se2/Cu2Se/In3Se2 sandwich structure deposited by thermal evaporation technique for CIS solar cells. The X-ray diffraction pattern reveals that annealing improves the crystallinity and the formation of CIS composites cross section SEM image the uniform distribution of crysatllite spread over entire substrate. Also a clear distinguished between subsequent layer is visible from the image. Photoluminescence (PL) study shows the formation of Cu2Se-In2Se composites. The Energy band gap value calculated for as deposited films is 2.49 eV and same upon annealing splitted into 1.57, 1.96 eV after annealing at 150° which is evident from UV visible spectrographs.