Preparation of Zn Doped Cu(In,Ga)Se2 Thin Films by Physical Vapor Deposition

Abstract

Cu(In,Ga)Se2 (CIGS) surface was modified with Zn doping using vacuum evaporation. The substrate temperature of CIGS films and exposed time during the deposition was changed to control the distribution of Zn in the CIGS films. The diffusion of Zn in CIGS film was observed at substrate temperature of over 200°C. The solar cell fabricated using the CIGS film modified with Zn showed an efficiency of 13.9 %, an open circuit voltage of 0.576 V, a short circuit current density of 34.9 mA/cm2, and a fill factor of 0.692. The effects of the amount and distribution of Zn on the performance of CIGS solar cells are discussed.