Research on Polycrystalline Thin-Film Submodules Based on CuInSe2 Materials: Final Subcontract Report, 11 November 1990 - 30 June 1995

This report describes work performed by Solarex Corporation to enter i nto the development of CIS-based photovoltaic (PV) products. The activity began with developing manufacturable deposition methods for all required thin-film layers and developing and understanding processes using those methods. It included demonstrating the potential for high conversion efficiency and followed with developingviable methods for module segment formation and interconnection. These process steps were integrated to fabricate monolithic CIS-based submodules. An important result of this program is the basis of understanding established i n developing this material for PV applications. This understanding is necessary to address issues of manufacturability and cost-which were recognized early in the programas being determined by successful solutions to issues of yield, reproducibility, and control as much as by material and energy costs, conversion efficiency, and process speed. Solarex identified at least one absorber formation process that is very robust to shunt formation from pinholes or point defects, tolerant of variation in processing temperature and elemental composition, and is capable ofproducing high conversion efficiency. This program also allowed development and scale-up of processes for the deposition of all other substrate, heterojunction buffer, and window layers and associated scribing/module formation operations to 1 000-cm2 size. At the completion of this program, Solarex has in place most of the necessary elements to begin the transition to pilot operation of CISmanufacturing activities.