12.29% Low Temperature–Processed Dopant‐Free CdS/p‐Si Heterojunction Solar Cells

Most crystalline silicon (c-Si) solar cells are based on high temperature-processed p-n junctions or highly doped heterojunctions. The concept of dopant-free carrier selective contact has become a research hotspot and been successfully demonstrated with n-type Si wafers, showing the great potential of simplified fabrication process and lower thermal-consuming. However, there are few successful cases on p-Si, dopant-free p-Si/CdS (cadmium sulfide)/ITO (indium tin oxide) solar cells with champion efficiency of 12.29% (device area 4 cm(2)) have been demonstrated with DC magnetron sputtered CdS thin films working as electron-selective contact. A proper annealing treatment is found essential in improving the p-Si/CdS/ITO heterocontact and device performance. The author's preliminary results confirm the feasibility of preparation of efficient p-Si wafer-based dopant-free solar cells.