Advanced CIGS Photovoltaic Technology: Final Subcontract Report, 15 November 2001--13 February 2005

The principal objective of Energy Photovoltaics, Inc., is to develop the best CIGS large-area module process based on capability of implementation on EPV's large-scale processing equipment. The first requirement was to develop recipes for CIGS, junction formation, and a high-quality ZnO window that together are capable of producing small-area devices with efficiencies in excess of 13%. The secondrequirement was to significantly improve the uniformity of all layers (Mo, CIGS, CdS, and ZnO) on large-area substrates. Thirdly, patterning procedures needed to be improved to generate an interconnection with the lowest possible contact resistance, to eliminate possible shunting paths, and to reduce the dead area. The processes should have good reproducibility and therefore be easilycontrollable. Finally, having assembled all of these aspects mentioned above, the goal was to fabricate large-area, monolithic CIGS modules with efficiencies in the range 7% - 10%. A study of module reliability and long-term stability would be conducted to establish the foundation and confidence for embarking on future manufacturing.