Amorphous silicon solar cells. Quarterly report No. 2, January 1-March 31, 1981
An analysis of the photoconductive response of Schottky-barrier and p-i-n solar cell structures shows that the photoconductivity determines the fill factor, rather than the dark current, as in crystalline silicon cells. An analysis of the I-V curves of p-i-n cells shows that the electron and hole drift lengths are comparable. High-conductivity p- and n-type films (sigma = 1-10 ..cap omega../sup -1/.cm/sup -1/) have been produced in an rf discharge for T/sub s/ > 400/sup 0/C and in a dc cathodic discharge for T/sub s/ > 350/sup 0/C. Some of these high-conductivity films are clearly microcrystalline, while others appear to be still amorphous. Diffusion lengths of approx. 0.8 ..mu..m have been measured in undoped a-Si:H films at illumination levels of approx. 0.1 Sun. The activation energy of the diffusion length is 0.28 eV. The technique for measuring the diffusion length has been improved by means of a liquid Schottky-barrier contact. Preliminary results confirm that carbon alloying of the p layer improves the performance of p-i-n cells illuminated through that layer. Tests on p-i-n cells with ITO contacts on both sides show that the stability is better for cells illuminated through the p layer. A statistical analysis of solar-cell data indicates that a major factor determining the efficiency of ITO/n-i-p cells is the ITO/n contact. Several parameters have been determined that affect device stability. A gradual boron profile enhances stability, as does a thin, undoped layer. Increased oxygen contamination increases the degradation of a-Si:H p-i-n cells.
- Research Organization:
- Solar Energy Research Inst., Golden, CO (USA); RCA Labs., Princeton, NJ (USA)
- DOE Contract Number:
- AC02-77CH00178
- OSTI ID:
- 5748424
- Report Number(s):
- SERI/PR-0-9372-2; ON: DE81030278
- Country of Publication:
- United States
- Language:
- English
Similar Records
Amorphous thin films for solar-cell applications. Quarterly report No. 1, 11 September-10 December 1979
Amorphous silicon solar cells. Quarterly report No. 3, 1 April 1981-30 June 1981
Related Subjects
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ACTIVATION ENERGY
ALLOYS
AMORPHOUS STATE
BORON ADDITIONS
BORON ALLOYS
CARBON ADDITIONS
CONTAMINATION
CRYSTAL DOPING
DEPOSITION
DIFFUSION LENGTH
DIMENSIONS
DIRECT ENERGY CONVERTERS
ELECTRIC CONDUCTIVITY
ELECTRIC CONTACTS
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ELEMENTS
ENERGY
EQUIPMENT
FABRICATION
FILMS
HOLES
HYDRIDES
HYDROGEN COMPOUNDS
JUNCTIONS
LENGTH
NONMETALS
OXYGEN
PERFORMANCE
PHOSPHORUS ADDITIONS
PHOTOCONDUCTIVITY
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PLASMA ARC SPRAYING
SCHOTTKY BARRIER SOLAR CELLS
SEMICONDUCTOR JUNCTIONS
SEMIMETALS
SILANES
SILICON
SILICON COMPOUNDS
SILICON SOLAR CELLS
SOLAR CELLS
SOLAR EQUIPMENT
SPRAY COATING
STABILITY
SURFACE COATING