Comparative study of conventional vs. one-step-interconnected (OSI) monolithic CdTe modules

We report on the fabrication of 5 × 7.5 cm² CdTe photovoltaic module devices using two alternative routes. One which uses the conventional approach where laser scribing and active layer deposition steps are inter-mixed, and the other via the one-step-interconnection (OSI) process. OSI combines three laser processes with two inkjet processes, depositing insulating and conductive materials. This allows the series interconnection to occur after the deposition of all active layers reducing fabrication time, capital equipment cost and interconnect dead zone. Its suitability for the manufacture of CdTe mini-modules has previously been demonstrated but no direct comparison was made against the conventional process. The structural properties and performance of conventional vs. OSI processed CdTe modules are presented and show comparable performance using both approaches with the OSI showing considerable process simplification.