Laser processing for monolithic interconnection of kesterite thin-film modules

Advanced photovoltaic cells use thin layers of emerging materials like Cu2ZnSnSe4(CZTSe) instead of silicon. This study explores laser processing for the monolithic interconnection of CZTSe thin-film modules using a picosecond-pulsed laser working at three different wavelengths (355 nm, 532 nm, 1064 nm) and two irradiation methods (direct laser irradiation and irradiation through the glass substrate). Three processes (P1, P2, P3) target various layers to interconnect adjacent solar cells. This work aims to optimize the process parameters for precise material removal with minimal underlying layer damage.