Zn/sub 3/P/sub 2/ as an improved semiconductor for photovoltaic solar cells. Ninth quarterly report, September 1, 1980-November 31, 1980
Frequency and voltage dependent capacitance measurements of ZnO/Zn/sub 3/P/sub 2/ heterojunctions have been made and the results interpreted according to a model which considers the total capacitance arising from contributions due to the depletion layer capacitance, interface charges and a dipole charge. The capacitance of the devices is anomalously high at low frequencies but agrees well with the value calculated from the bulk carrier density at 1 MHz. The data suggest a significant contribution to the capacitance from the charging and discharging of interface states. Direct evidence for a relationship between defects in the Zn/sub 3/P/sub 2/ (grains boundaries, dislocations, etc.,) and the collected current have been found by comparing EBIC images of ZnO/Zn/sub 3/P/sub 2/ devices with the etched surfaces of the samples. The series resistance of thin film Zn/sub 3/P/sub 2/ devices has been analyzed and the origin of the series resistance considered. A new substrate consisting of sequentially deposited layers of Fe and Si on mica has resulted in improved device performance. Devices with a conversion efficiency as high as 2.7% have been obtained. Fill factors in excess of 50% have been obtained for the first time. The diffusion coefficient of magnesium has been measured to 100/sup 0/C and 125/sup 0/C using a spectral response method. A model including contributions from both diffusion and space charge recombination terms was utilized to calculate the open circuit voltage and short circuit current as a function of junction depth of the n on p devices. A comparison of the experimental J/sub sc/ and V/sub oc/ as a function of junction depth was made by characterizing the devices after successive surface diffusions. Results are presented and disucssed. (WHK)
- Research Organization:
- Delaware Univ., Newark (USA). Inst. of Energy Conversion
- DOE Contract Number:
- AC02-76CH00178
- OSTI ID:
- 6535051
- Report Number(s):
- SERI/PR-9062-1-T5
- Country of Publication:
- United States
- Language:
- English
Similar Records
Zn/sub 3/P/sub 2/ as an improved semiconductor for photovoltaic solar cells. Eighth quarterly report, June 1-August 31, 1980
Zn/sub 3/P/sub 2/ as an improved semiconductor for photovoltaic solar cells. Tenth quarterly report, December 1, 1980-February 28, 1981
Related Subjects
36 MATERIALS SCIENCE
ZINC PHOSPHIDE SOLAR CELLS
FABRICATION
PERFORMANCE
ZINC PHOSPHIDES
CRYSTAL DEFECTS
SEMICONDUCTOR JUNCTIONS
CARRIER DENSITY
CHARGE COLLECTION
DEPLETION LAYER
DESIGN
DIFFUSION
DISLOCATIONS
EFFICIENCY
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
ELECTRON SCANNING
EXPERIMENTAL DATA
FILL FACTORS
GRAIN BOUNDARIES
GRAPHS
MAGNESIUM
MATHEMATICAL MODELS
P-N JUNCTIONS
SUBSTRATES
TABLES
THEORETICAL DATA
ZINC OXIDES
ALKALINE EARTH METALS
CHALCOGENIDES
CRYSTAL STRUCTURE
CURRENTS
DATA
DIRECT ENERGY CONVERTERS
ELEMENTS
EQUIPMENT
INFORMATION
JUNCTIONS
LAYERS
LINE DEFECTS
METALS
MICROSTRUCTURE
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHOSPHIDES
PHOSPHORUS COMPOUNDS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PNICTIDES
SOLAR CELLS
SOLAR EQUIPMENT
ZINC COMPOUNDS
140501* - Solar Energy Conversion- Photovoltaic Conversion
360602 - Other Materials- Structure & Phase Studies