Photovoltaic mechanisms in polycrystalline thin-film solar cells. Final report, 28 September 1978-28 September 1979

Technical Report · Sat Mar 01 04:00:00 EST 1980

OSTI ID:5266549

Zanio, K

Studies were undertaken to examine grain boundaries in polycrystalline material and apply these results to the development of thin-film solar cells using InP as the absorber layers. A model was developed which related material parameters to leakage currents in a thin-film polycrystalline p-n junction. In this model, the grain boundary was treated as a semiconductor with bandgap lower than that of the surrounding bulk. Since a leakage current at the grain boundary might decrease for a wider bandgap material, InGaP was considered and deposited by planar reactive deposition (PRD) on a single-crystal InP and lattice-matched GaAs. X-ray analysis and Hall measurements indicated that the quality of the epitaxy on GaAs was superior to that on InP, presumably due to a closer lattice match. Parallel etching studies to preferentially remove the grain boundaries showed that a 5HCl: 3HNO/sub 3/ : 4HF etch was highly selective in attacking the grain boundaries in bulk polycrystalline InP. Canyons with depths greater than 10 ..mu..m and widths on the order of 1 ..mu..m are the most common form of attack.

• Research Organization: Hughes Research Labs., Malibu, CA (USA)
• DOE Contract Number: AC01-78ET20544
• OSTI ID: 5266549
• Report Number(s): DOE/ET/20544-T1; ON: DE84009522
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
CRYSTAL STRUCTURE
CRYSTALS
CURRENTS
DIRECT ENERGY CONVERTERS
ELECTRIC CURRENTS
EQUIPMENT
ETCHING
FILMS
GRAIN BOUNDARIES
INDIUM PHOSPHIDE SOLAR CELLS
LEAKAGE CURRENT
MATHEMATICAL MODELS
MICROSTRUCTURE
PASSIVATION
PERFORMANCE
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
POLYCRYSTALS
SOLAR CELLS
SOLAR EQUIPMENT
SURFACE FINISHING
THIN FILMS