PVMaT Cost Reductions in the EFG High Volume PV Manufacturing Line: Final Subcontract Report, 5 August 1998 -- 4 February 2001

This report describes the three major task areas: manufacturing systems development, low-cost processing technology, and flexible manufacturing methods. In Manufacturing Systems, we have worked on implementing and utilizing SPC on a larger scale by developing support systems for computer-aided data bases and equipment and process-tracking methodology; developing and implementing new diagnostictechniques; reducing acid use and waste products by introducing a new dry-etch process; and formalizing documentation and training procedures for manufacturing processes (ISO 9000) and for waste product and safety management (ISO 14000) to assist in handling the larger manufacturing organization. Low-Cost Processes, we report on progress in demonstrating low-damage, high-throughput lasertechnology; studies on Rapid Thermal Processing approaches to improving cell efficiency; evaluating new thin-wafer technology using EFG cylinders; and developing a large EFG octagon and laser-cutting technology for producing 12.5 cm x 12.5 cm wafers. For Flexible Manufacturing, we completed introduction of manufacturing data bases for wafer and cell manufacturing; process modifications toaccommodate manufacture of 10 cm x 15 cm wafers; and module field-performance studies and defect tracking to be used to improve manufacturing processes, new encapsulant qualification and introduction into manufacturing, and progress in developing designs for low-cost modules.