Cadmium sulfide/copper sulfide heterojunction cell research. Final report, July 1, 1977-August 31, 1978

Technical Report · Tue May 01 04:00:00 EDT 1979

OSTI ID:5199786

Meakin, J D

Thin film CdS/Cu/sub 2/S solar cells have been produced with energy conversion efficiencies up to 9.15% as measured in natural sunlight. The yield of cells has been maintained at a high level and out of a group of 65 cells that were completed with an anti-reflection coating over 92% had efficiencies above 7%, 72% exceeded 8% and 11% exceeded 9%. Cells based on the modified heterojunction (CdZn)S/Cu/sub 2/S are also under development and have now reached efficiencies of 7.4%. A technique has been developed to produce homogeneous films of (CdZn)S with controlled composition and low resistivities suitable for high efficiency solar cells. Both cell development programs continue to be driven by the loss minimization methodology. In addition to providing direction and feedback to the cell production efforts, the accompanying analysis has established that the limit on achievable cell efficiency is in the range of 11 to 12% for CdS/Cu/sub 2/S and 14 to 16% for (CdZn)S/Cu/sub 2/S. The model of cell structure and operation has been refined and further quantified. A technique has been developed to give a direct measure of the carrier losses at the junction. The functional dependence of the interface recombination rate, junction field and collected current has been derived and experimentally confirmed. The importance of hole traps in the CdS has been shown and some progress made in relating the trap population to the CdS growth conditions. Further demonstration of reversibility of Cu/sub 2/S oxidation has been made and related to the long-term stability of CdS/Cu/sub 2/S cells. The necessary cell design changes to further improve the CdS/Cu/sub 2/S cell efficiency have been identified and a program planned for its achievement.

• Research Organization: Delaware Univ., Newark (USA). Inst. of Energy Conversion
• OSTI ID: 5199786
• Report Number(s): SAN-1576-3
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ANTIREFLECTION COATINGS
CADMIUM COMPOUNDS
CADMIUM SULFIDE SOLAR CELLS
CADMIUM SULFIDES
CHALCOGENIDES
COATINGS
COPPER COMPOUNDS
COPPER SULFIDES
CRYSTALS
CURRENTS
DATA
DATA FORMS
DESIGN
DIRECT ENERGY CONVERTERS
EFFICIENCY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
EQUIPMENT
FABRICATION
FILL FACTORS
FILMS
GRAPHS
HOLES
INFORMATION
INORGANIC PHOSPHORS
OPTIMIZATION
PERFORMANCE
PHOSPHORS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
POLYCRYSTALS
RECOMBINATION
RESEARCH PROGRAMS
SOLAR CELLS
SOLAR EQUIPMENT
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TRAPS
ZINC COMPOUNDS
ZINC SULFIDES