Zn/sub 3/P/sub 2/ as an improved semiconductor for photovoltaic solar cells. Thirteenth quarterly report, September 1, 1981-November 30, 1981

Technical Report · Mon Feb 01 04:00:00 EST 1982

OSTI ID:5288947

Bhushan, M; Meakin, J D; Pawlikowski, J M

Efforts to produce bulk n-type Zn/sub 3/P/sub 2/ by incorporating Mg as an impurity have so far resulted in high resistivity p-type material. On the basis of the capacitance voltage characteristics of Mg diffused Zn/sub 3/P/sub 2/ devices, a model in which Mg compensates the acceptor levels, creating a thin insulating region near the surface, was developed. In order to test the validity of this model, the thickness of the Mg diffused layer was measured by first heating a Mg/Zn/sub 3/P/sub 2/ device to produce approx. 50 ..mu..m thick Mg diffused layer and then measuring the device characteristics after successively removing a few ..mu..m of the surface at a time. This experiment confirmed the results reported earlier on the basis on n/p junction formation. A study of the native oxide of Zn/sub 3/P/sub 2/ produced by thermal oxidation was conducted for the development of MIS solar cells. The oxidized surface was composed of ZnO and P/sub 2/O/sub 5/ and was found to contain excess zinc. The as-grown oxide layer in Zn/sub 3/P/sub 2/ was electrically conducting and, therefore, not suitable for MIS cells. MIS cells produced by plasma oxidation of Zn/sub 3/P/sub 2/ had V/sub oc/ approx. 0.5 Volts and J/sub 0/ approx. 10/sup -9/ Amp/cm/sup 2/. A software package to store, sort and retrieve the data generated by the production and testing of Zn/sub 3/P/sub 2/ thin-film cells was developed. ZnSe/Zn/sub 3/P/sub 2/ heterojunction devices prepared by vacuum evaporation of ZnSe had a maximum V/sub oc/ of 0.36 Volts and J/sub sc/ in the range of 0.1 and 0.7 mA/cm/sup 2/. The resistivity of ZnSe films was lowered by annealing in the presence of zinc vapor at 400/sup 0/C. Al doping in ZnSe gave very leaky diodes and a lower V/sub oc/. Optical absorption measurements were made on thin ZnSe films deposited on glass by vacuum evaporation and close-spaced vapor transport.

• Research Organization: Solar Energy Research Inst., Golden, CO (USA); Delaware Univ., Newark (USA). Inst. of Energy Conversion
• DOE Contract Number: AC02-77CH00178
• OSTI ID: 5288947
• Report Number(s): SERI/PR-8062-1-T15; ON: DE82014367
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
ABSORPTION
ALKALINE EARTH METALS
ALUMINIUM
ANNEALING
BAND THEORY
CAPACITANCE
CHALCOGENIDES
CHEMICAL REACTIONS
COMPUTER CODES
CRYSTAL DOPING
CURRENT DENSITY
DIFFUSION
DIRECT ENERGY CONVERTERS
ELECTRIC CONDUCTIVITY
ELECTRIC POTENTIAL
ELECTRICAL PROPERTIES
ELEMENTS
EQUIPMENT
EVAPORATION
FABRICATION
HEAT TREATMENTS
HETEROJUNCTIONS
HOMOJUNCTIONS
JUNCTIONS
MAGNESIUM
MATHEMATICAL MODELS
METALS
MIS SOLAR CELLS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PHOSPHORUS OXIDES
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PNICTIDES
SELENIDES
SELENIUM COMPOUNDS
SEMICONDUCTOR JUNCTIONS
SOLAR CELLS
SOLAR EQUIPMENT
TESTING
VACUUM EVAPORATION
VALIDATION
ZINC COMPOUNDS
ZINC OXIDES
ZINC PHOSPHIDE SOLAR CELLS
ZINC PHOSPHIDES
ZINC SELENIDES