Application of laser annealing and laser-induced diffusion to photovoltaic conversion

Conference · Thu Dec 10 04:00:00 EST 1981

OSTI ID:5618923

Young, R T; van der Leeden, G A; Wood, R F

High efficiency silicon solar cells can be fabricated by ion implantation followed by pulsed laser annealing. The proper choice of implantation parameters (energy and dose), laser energy density, substrate temperature, etc., and the improvement of the minority carrier diffusion length of the starting material are important factors in obtaining high efficiency cells. Recently, it has been shown that substrate heating during pulsed laser annealing can improve the electrical properties of the emitter regions of solar cells. It has also been found that the open circuit voltage and the fill factor of ion-implanted, laser-annealed cells can be improved by increasing the emitter dopant concentration, whereas the short circuit current remains fairly constant; these results are in only qualitative agreement with theoretical predictions. By using ion implantation followed by laser annealing to form p-n junctions, laser damage gettering to enhance the minority carrier diffusion length, and laser-induced diffusion for incorporating back surface fields, single crystal Si solar cells with efficiencies of over 16% AMI have been obtained. Similar methods are now being applied in the fabrication of polycrystalline cells from Wacker and small-grained (50 ..mu..m) thin-film material. The rationale for these studies and the results obtained to date will be discussed.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5618923
• Report Number(s): CONF-811224-1; ON: DE82006792
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ANNEALING
CARRIER DENSITY
CHARGE CARRIERS
CRYSTAL DOPING
CRYSTALS
CURRENTS
DIFFUSION
DIFFUSION LENGTH
DIMENSIONS
DIRECT ENERGY CONVERTERS
EFFICIENCY
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRIC POTENTIAL
ELECTRICAL PROPERTIES
EQUIPMENT
FABRICATION
FILL FACTORS
GETTERING
HEAT TREATMENTS
HEATING
ION IMPLANTATION
JUNCTIONS
LASER-RADIATION HEATING
LENGTH
MONOCRYSTALS
P-N JUNCTIONS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PLASMA HEATING
POLYCRYSTALS
SEMICONDUCTOR JUNCTIONS
SILICON SOLAR CELLS
SOLAR CELLS
SOLAR EQUIPMENT
SPECTRAL RESPONSE