Site selective doping of Zn for the p‐type Cu(In,Ga)Se2 thin film for solar cell application

Selective doping of a Zn impurity at the group III site in a Cu(In, Ga)Se 2 (CIGS) film was performed by the doping of Zn at the first stage of the three‐stage method. The p ‐type CIGS:Zn film was obtained, which is in contrast to the n ‐type CIGS:Zn film obtained by the Zn impurity doping at the second and third‐stages. Based on excitation intensity dependence of photoluminescence (PL) at low‐temperature, the change in the acceptor level was observed. The enhancement of carrier concentration as a result of Zn‐doping in the p ‐type CIGS:Zn film was observed. The CIGS:Zn solar cells exhibited η of 14.5% and V oc of 0.658 V, which are higher than that of the corresponding solar cells using the undoped CIGS films