Solution processing of CuIn(S,Se)2 and Cu(In,Ga)(S,Se)2 thin film solar cells using metal chalcogenide precursors

In order to realize the true low cost potential of Cu(In,Ga)(S,Se)2 (CIGS) thin film solar cells, high performance needs to be combined with simple and easily controllable atmospheric-based deposition processes. A molecular solution-based approach for CIGS deposition is proposed, using metal chalcogenide precursors dissolved in an amine-thiol solvent combination. CIGS thin films were sprayed with varying Ga content and the sprayed films were incorporated into solar cells. The effect of the Ga content on the material and device properties is investigated. A champion power conversion efficiency of 9.8% (active area) was achieved, which highlights the potential of this methodology.