TOWARDS MODULE EFFICIENCIES OF 16 % WITH AN IMPROVED CIGSSe DEVICE DESIGN

ABSTRACT: Cu(In,Ga)(S,Se)2 (CIGSSe) thin film modules based on the AVANCIS SEL-RTP process (stacked elemental layer – rapid thermal processing) are commercially available under the brand name PowerMax ® in six different nominal power classes up to 135W, corresponding to a maximum aperture efficiency of 14.2%. In order to further catch up with multicrystalline silicon based solar modules we investigate advanced CIGSSe process and device designs in the AVANCIS R&D pilot line on 30*30cm2-sized substrates. With the improved CIGSSe device design which is the subject matter of the present publication we were able to further enhance the aperture area efficiency to an independently confirmed value of 15.5%. We report on the individual measures of the improved CIGSSe device design which resulted in an enhancement mainly of the fill factor FF. The efficiency improvement is achieved without compromising on the long-term stability of the electrical performance parameters as demonstrated by the results of a damp heat testing of several prototypes with the improved CIGSSe device design yielding comparable long-term stability data to our standard baseline products. Along the routes described above the efficiency evolution further continues with the latest champion module coming from our line showing an independently certified aperture area efficiency of 15.8%