Laser processing of silicon solar cellsResults of a study to utilize an Nd:glass laser for production line annealing of ion implantation induced damage in solar cells are reported. Czochralski-grown and sawn Si wafers 7.6 cm in diam, 0.35 mm thick, were implanted with phosphorus junctions and boron BSFs. Annealing with electron beam, laser, and firing of an Al paste to form the BSFs in different cells was compared. The laser was employed at 1.06 and 0.53 micron and in combination of both, with a 20-50 nsec pulsewidth, and energy densities of 1.2, 1.5, 1.9, and 2.1 J/sq cm. Best optical coupling was observed with the combined wavelengths and a 20 nsec pulse, using energy densities less than 1.5 J/sq cm. Although the Al sintered cells displayed the best characteristics, laser annealing is concluded to offer electrically active, defect-free, shallow junction Si substrates for high efficiency cells.
Document ID
19820061461
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Katzeff, J. S. (Lockheed Missiles and Space Co. Sunnyvale, CA, United States)
Lopez, M. (Lockheed Missiles and Space Co., Inc. Sunnyvale, CA, United States)
Burger, D. R. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena CA, United States)