Numerical analysis of a highly efficient CdTe/CdS:O solar cell with BSF

The polycrystalline cadmium telluride is known as one of the leading photovoltaic materials due to its superior optoelectronic properties and possibilities of cost effective fabrication. It has a direct bandgap of 1.45 eV and absorption coefficient over 5x105 /cm. It was investigated the possibility of using double buffer layer and BSF to increase the cell performance by numerical analysis with SCAPS-1D simulator. The CdTe absorption layer was reduced to 1 μm only with ZnTe as BSF layer. The Viability of using double buffer layer of ZnO and Zn2SnO4 was examined and it showed maximum conversion efficiency of 26.34% (Voc= 1.07 V, Jsc=28.7771 mA/cm2, FF= 85.04%). The proposed cell structure is (Glass/SnO2/Zn2SnO4/ ZnO/ CdS:O/ CdTe /ZnTe /Ni).The thermal stability was investigated and shown temperature coefficient of -0.268 %/°C which clearly indicate the better stability of the proposed cell.