Amorphous-silicon solar cells. Annual report, July 1, 1976--June 30, 1977

Technical Report · Thu Sep 01 04:00:00 EDT 1977

OSTI ID:6411146

Carlson, D E

Amorphous-silicon solar cells have been fabricated with conversion efficiencies as high as 6% in AM1 sunlight. The best values of the open-circuit voltage, short-circuit current density and fill factor are 895 mV, 14.5 mA/cm/sup 2/, and 0.674, respectively. Pd-Schottky-barrier cells have shown no degradation in conversion efficiency after 9700 h of constant illumination of approx. 50 to 75 mW/cm/sup 2/, and p-i-n cells have remained stable after more than 23 months on the shelf. Discharge-produced a-Si used in efficient solar cells contains approx. 10 to 30 at. % of bonded hydrogen. Infrared absorption and photoluminescence measurements indicate that the films with the lowest defect densities are deposited at substrate temperatures in the range of 300 to 350/sup 0/C. Hydrogen out-diffusion at higher temperatures apparently creates defect stages such as dangling bonds. Photoconductivity measurements and light-pulse experiments indicate electron and hole lifetimes of approx. 1 to 40 ..mu..s. Light-pulse experiments yield electron drift mobilities of approx. 2-5 x 10/sup -2/ cm/sup 2//V-s and hole drift mobilities of approx. 6 x 10/sup -4/ cm/sup 2//V-s. Both techniques find an electron trap approx. 0.20 to 0.25 eV below the conduction band and a hole trap approx. 0.35 to 0.40 eV above the valence band.

• Research Organization: RCA Labs., Princeton, NJ (USA)
• OSTI ID: 6411146
• Report Number(s): SAN-1286-4
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
AMORPHOUS STATE
CARRIER LIFETIME
CARRIER MOBILITY
DIRECT ENERGY CONVERTERS
EFFICIENCY
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRONS
ELEMENTARY PARTICLES
FABRICATION
FERMIONS
HOLES
LEPTONS
LIFETIME
LUMINESCENCE
MOBILITY
PHOTOCONDUCTIVITY
PHOTOELECTRIC CELLS
PHOTOLUMINESCENCE
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
SCHOTTKY BARRIER DIODES
SEMICONDUCTOR DEVICES
SEMICONDUCTOR DIODES
SILICON SOLAR CELLS
SOLAR CELLS
SUBSTRATES