PV Cz silicon manufacturing technology improvements. Semiannual subcontract report, 1 April 1994--30 September 1994

This describes work done in the final phase of a 3-y, 3-phase contract to demonstrate cost reductions and improvements in manufacturing technology. The work focused on near-term projects in the SSI (Siemens Solar Industries) Czochralski (Cz) manufacturing facility in Camarillo, CA; the final phase was concentrated in areas of crystal growth, wafer technology, and environmental, safety, and health issues. During this period: (1) The crystal-growing operation improved with increased growth capacity. (2) Wafer processing with wire saws continued to progress; the wire saws yielded almost 50% more wafers per inch in production. The wire saws needs less etching, too. (3) Cell processing improvements focused on better handling and higher mechanical yield. The cell electrical distribution improved with a smaller standard deviation in the distribution. (4) Module designs for lower material and labor costs continued, with focus on a new junction box, larger modules with larger cells, and less costly framing techniques. Two modules demonstrating these cost reductions were delivered during this phase