Prediction of photovoltaic Cu(In,Ga)Se2 p-n device performance by forward bias electrochemical analysis of only the p-type Cu(In,Ga)Se2 films
Authors
D. Colombara, T. Bertram, V. Depredurand, T. Fouquet, J. Bour, C. Broussillou, P. P. Grand, and P. J. Dale
Reference
ECS Transactions, vol. 66, no. 6, pp. 19-25, 2015
Description
This work is an attempt to rate the quality of Mo/Cu(In,Ga)Se2 films intended for fabrication of photovoltaic devices. The procedure is based on the simple current-voltage electrochemical analysis of the bilayer in a Eu2+/3+-containing electrolyte solution. Two series of bilayer samples were tested electrochemically, while sister samples were completed into Mo/Cu(In,Ga)Se2/CdS/i-ZnO/Al:ZnO/Ni-Al solid state devices and their current-voltage characteristics measured in the dark. A correlation was found between the reverse saturation current density of the solid state devices and an analogous parameter extracted from the electrochemical response in forward bias. While Eu2+ was found to be metastable in water posing restrictions to the application, reproducible measurements were achieved with a methanol-based solution. The intrinsic simplicity of the proposed methodology makes it particularly suitable for the implementation of a low-cost diagnostic tool.
