Design and simulation of an efficient solar cell with Sb2Se3 and CdTe as double absorber layers

The present study proposes a solar cell using double absorber layers of Sb2Se3 and CdTe. The design aim is to obtain high efficiency while maintaining or improving other main characteristics of solar cell. The proposed Sb2Se3/CdTe/CdS/ZnO/SnO2 solar cell include additional Sb2Se3 layer compared with its conventional counterpart while their total thickness is equal. The SCAPS simulator software has been applied to investigate the device performance. Firstly, the impacts of applying two absorber layers on the cell's performance and their thickness ratio were studied. Then, the effect of limitations such as band gap energy and the impurity concentration of the Sb2Se3 layer, the work function of the back contact metal, and the operating temperature on the cell performance were investigated. For thickness of 1.3 ?m of Sb2Se3 layer and 0.7 ?m of CdTe layer, the efficiency of 32.40% was obtained. The short circuit current density is JSC=34.55 mA/cm2, the open circuit voltage Voc = 1.06 V, and the Fill Factor is FF = 86.06%. The obtained efficiency is about 5% higher than the structure where only the layer of CdTe is applied as the absorber. Also, the use of Te which is a limited supply material in environment is reduced in proposed structure. Simulation results demonstrate that a solar cell with higher efficiency and more compatible with environment can be achieved using the proposed two absorber layer.