Amorphous thin films for solar-cell applications. Final report, 11 September 1979-10 September 1980
The drift mobility has been measured in doped amorphous silicon by measuring the current transient in a Schottky-barrier device during a reverse-bias voltage pulse. The drift mobility is approx. 6.5 x 10/sup -3/ cm/sup 2//V-s at room temperature. Mass spectroscopy studies indicate that the film growth cannot be a simple ion-surface recombination process but is probably due to either thermal decomposition of higher silanes or free radical-surface reaction. The photoelectromagnetic effect has been used to measure the hole diffusion length in undoped a-Si:H. Another technique that has been recently developed at RCA involves surface photovoltage profiling of solar-cell structures. This technique involves the use of a vibrating probe in conjunction with an argon sputtering beam to probe the field distribution of p-i-n cells. Preliminary measurements of the Hall effect in p-type a-Si:H yield a value of approx. 2 x 10/sup -2/ cm/sup 2/ /V-s at 100/sup 0/C with an activation energy of 0.45 eV. Electron irradiation studies show that the threshold energy for electron bombardment damage is more than 10/sup 2/X less than in crystalline Si. A detailed study of the effects of adding various fluorine-containing gases (SiF/sub 4/, HF and F/sub 2/) to silane discharges showed that the device performance is adversely affected. A detailed description of an experimental optimization technique for both a-Si:H materials and solar cells is given. This technique utilizes samples made with graded deposition conditions and characterized with automated testing equipment. These procedures have helped to develop two different types of p-i-n solar cells with conversion efficiencies in the 5 to 6% range. It was shown that interference fringes in the collection efficiency of a-Si:H solar cells can give useful information concerning the transport in gap states.
- Research Organization:
- RCA Labs., Princeton, NJ (USA)
- DOE Contract Number:
- AC02-77CH00178
- OSTI ID:
- 6662732
- Report Number(s):
- SERI/PR-0-8254-F
- 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 thin films for solar-cell applications. Quarterly report No. 2, 11 December 1979-10 March 1980
Related Subjects
36 MATERIALS SCIENCE
SILICON
CARRIER MOBILITY
DIFFUSION LENGTH
PLASMA ARC SPRAYING
SILICON SOLAR CELLS
FABRICATION
PHYSICAL RADIATION EFFECTS
AMORPHOUS STATE
DATA
EFFICIENCY
ELECTRONS
FILMS
FLUORINE ADDITIONS
GLOW DISCHARGES
GRAPHS
HALL EFFECT
HOLES
HYDROGEN ADDITIONS
MATHEMATICAL MODELS
PERFORMANCE
RESEARCH PROGRAMS
SPECTRAL RESPONSE
DEPOSITION
DIMENSIONS
DIRECT ENERGY CONVERTERS
ELECTRIC DISCHARGES
ELEMENTARY PARTICLES
ELEMENTS
EQUIPMENT
FERMIONS
INFORMATION
LENGTH
LEPTONS
MOBILITY
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
RADIATION EFFECTS
SEMIMETALS
SOLAR CELLS
SOLAR EQUIPMENT
SPRAY COATING
SURFACE COATING
140501* - Solar Energy Conversion- Photovoltaic Conversion
360601 - Other Materials- Preparation & Manufacture