Thin-film polycrystalline silicon solar cells. Quarterly report No. 1, September 11-December 10, 1978

Technical Report · Mon Jan 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/5199769· OSTI ID:5199769

Faughnan, B. W.

A total of 16 solar cells was fabricated in the first quarter. Half of these had diffused junctions and half had ion-implanted junctions. In each group of eight, six were made on Wacker Silso polycrystalline substrates and two on control single-crystal wafers. The solar-cell parameters were measured for all cells. The efficiencies of the control wafers were as high as 12.7% with antireflection (AR) coating, whereas the highest efficiency of a cell made on Wacker material was 11.1% for a diffused-junction cell. The ion-implanted cells made with the Wacker material had systematically lower efficiencies, 5.9% versus 7.4% for diffused-junction cells without AR coating. Quantum efficiency versus wavelength was measured on all cells, and these curves were fit to a simple model solar cell. From this fit the minority carrier diffusion length in the base was obtained. A laser scanning apparatus was built which has a 4.5-..mu..m spot size. The solar cell under test is mechanically scanned across this focused laser spot. Laser scans were obtained over a 5 x 6-mm area on two solar cells. Comparison of the laser scan map with a photograph of the same region shows the same geometrical pattern of grain boundary lines. However, in the laser scan map, some of the grain boundaries are missing.

• Research Organization: RCA Labs., Princeton, NJ (USA)
• OSTI ID: 5199769
• Report Number(s): SAN-1876-1
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ANTIREFLECTION COATINGS
COATINGS
CRYSTAL STRUCTURE
CRYSTALS
DIFFUSION
DIFFUSION LENGTH
DIRECT ENERGY CONVERTERS
EFFICIENCY
EQUIPMENT
FABRICATION
GRAIN BOUNDARIES
INSPECTION
ION IMPLANTATION
JUNCTIONS
LASERS
MICROSTRUCTURE
PERFORMANCE
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
POLYCRYSTALS
QUANTUM EFFICIENCY
SEMICONDUCTOR JUNCTIONS
SILICON SOLAR CELLS
SOLAR CELLS
SOLAR EQUIPMENT
SPECTRAL RESPONSE