Effect of Thermally Evaporated n-CdTe Thin Film for Homojunction CdTe Solar Cell

Abstract

Cadmium Telluride (CdTe) is the most useful and very attractive binary semiconductor materials and it is renowned as a very favorable absorber material aimed at thin-film photovoltaic applications due to its optoelectronic properties. In this work, a three-layer of n-CdS, n-CdTe and p-CdTe films were deposited by different techniques for the fabrication of homojunction (Glass/FTO/n-CdS/n-CdTe/p-CdTe/Au) CdTe solar cell. The n-CdS and n-CdTe thin films were deposited by thermal evaporation (TE) techniques for different source to substrate distance (Δd) whereas a p-CdTe thin film was deposited by close spaced sublimation (CSS). The electrical properties of the as-deposited films were investigated by Hall Effect measurement system. The structural properties of n-CdTe thin films were studied by X-ray diffraction (XRD). Experimentally found electrical properties of the as-deposited n-CdS, n-CdTe and p-CdTe films were used for the numerical analyses. The numerical analysis was done by SCAPS-1D software to investigate the performance of Glass/FTO/n-CdS/n-CdTe/p-CdTe/Au device structure. The simulation results showed that the propose homojunction CdTe solar cell attained the cell conversion efficiency of 17.14%, an open circuit voltage (Voc) is of 0.88 V, a current density, Jsc is of 27.88 mA/cm2 and a fill factor of 66.32% at 1.5 AM solar irradiance.