Series Interconnection of Monolithic 2-Terminal CIGSe-Perovskite Tandem Cells: Development of a Novel Interconnection Scheme and Laser-based Patterning Processes

Perovskite and CIGSe are suitable partners for tandem solar cells, since the bandgap energies of both materials can be precisely adjusted. The fabrication of series-interconnected CIGSe-perovskite tandem solar cells requires a re-design of the series interconnection scheme for single junction cells and the development of the corresponding laser parameters for patterning. In this contribution, we present such a concept based on the evolution of the standard P1-P3 patterning design to a four-scribe line scheme by adding an additional isolation-cut (iso-cut) to separate the conductive intermediate window layer stack. To realize this interconnection scheme, laser-based processes for each individual patterning step were developed and suitable process windows were identified and evaluated.