EFFECTS OF THE ANNEALING TEMPERATURE AND CDCL2 TREATMENT ON THE PHOTOVOLTAIC PROPERTIES OF THE CDS CDTE SOLAR-CELL/

Effects of the annealing temperature and CdCl2 treatment of CdTe films prepared by vacuum evaporation on structural properties of the CdTe f ilms and photovoltaic properties of thin film CdS/CdTe solar cells wer e investigated. The crystal structure of as-deposited CdTe films was z incblende type with preferential orientation of the (111) plane parall el to the substrate. The preferential orientation of the (111) plane i n CdTe films decreased, and the grain size of CdTe films increased wit h the increase of the annealing temperature and the CdCl2 treatment. A s increasing annealing temperature, the conversion efficiency of the C dS/CdTe solar cells without and with CdCl2 was increased due to increa sing grain size and improving crystalline of CdTe films. However, the efficiency of cells annealed at the temperature of higher than 500 deg rees C for cells without CdCl2 treatment and 450 degrees C for cells w ith CdCl2 treatment was reduced because of increasing reverse saturati on current density and series resistance.