Preparation and properties of evaporated CdTe films compared with single-crystal CdTe. Progress report no. 6, February 1, 1982-April 30, 1982
Films of n-type CdTe:In have been deposited by hot-wall vacuum evaporation (HWVE) on 7059 glass substrates, BaF/sub 2/ single crystal substrates, metal (Pt, Cr, Mo, Al) coated glass substrates, and single crystal p-type CdTe substrates. Films deposited on 7059 glass show typically a dark resistivity of 2 x 10/sup 5/ ohm-cm and a light resistivity of 3 x 10/sup 2/ ohm-cm. With increasing In source temperature, the resistivity decreases, but actually increases slightly again if the T/sub In/ is raised above 600/sup 0/C. Photoexcitation increases the electron density but does not affect the electron mobility. It appears that the grains are depleted in the dark. Films deposited on BaF/sup 2/ show dark resistivity of about 5 ohm-cm and light resistivity of about 2 ohm-cm, corresponding to electron densities of about 3 x 10/sup 16/ cm/sup -3/ and electron mobilities of about 30 cm/sup 2//V-sec. For doping levels abpove 10/sup 16/ cm/sup -3/ photoexcitation increases the mobility, but not the electron density; it appears that the grains are not depleted in the dark in this case. Cr coated 7059 glass makes an ohmic contact to n-type CdTe films. A Schottky diode formed with a 100A thick Au layer showed V/sub oc/ = 0.46 V, J/sub sc/ = 9 mA/cm/sup 2/ and a solar efficiency of about 2%. An n/p homojunction device was made by HWVE deposition of a 1.5 ..mu..m thick n-type CdTe layer on a p-type CdTe single crystal substrate. Values of V/sub oc/ = 0.73 V and J/sub sc/ = 0.24 mA/cm/sup 2/ were obtained. Grain boundary investigations showed the additive quality of two independent grain boundaries when measured in series, and tested the effects of passivation by Au, Cu, Li and H/sub 2/ in p-type CdTe grain boundaries, and In in n-type CdTe grain boundaries. Marked decreases in grain boundary resistance were observed after Li diffusion and H/sub 2/ diffusion in p-type CdTe.
- Research Organization:
- Solar Energy Research Inst. (SERI), Golden, CO (United States); Stanford Univ., CA (USA). Dept. of Materials Science and Engineering
- DOE Contract Number:
- AC02-77CH00178
- OSTI ID:
- 5357460
- Report Number(s):
- SERI/PR-9330-1-T6; ON: DE82017062
- Resource Relation:
- Other Information: Portions of document are illegible
- Country of Publication:
- United States
- Language:
- English
Similar Records
Grain boundary phenomena in n-type CdTe films grown by hot wall vacuum evaporation
Preparation and properties of evaporated CdTe films compared with single-crystal CdTe. Progress report No. 5, November 1, 1981-January 31, 1982
Related Subjects
CADMIUM TELLURIDE SOLAR CELLS
PERFORMANCE
CADMIUM TELLURIDES
GRAIN BOUNDARIES
VACUUM EVAPORATION
ALUMINIUM
BARIUM FLUORIDES
CARRIER DENSITY
CARRIER MOBILITY
CHROMIUM
CURRENT DENSITY
ELECTRIC CONDUCTIVITY
ELECTRIC POTENTIAL
ELECTRONS
GLASS
HOMOJUNCTIONS
INDIUM
MOLYBDENUM
MONOCRYSTALS
PASSIVATION
PLATINUM
QUANTUM EFFICIENCY
SCHOTTKY BARRIER SOLAR CELLS
TEMPERATURE EFFECTS
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CADMIUM COMPOUNDS
CHALCOGENIDES
CRYSTAL STRUCTURE
CRYSTALS
DIRECT ENERGY CONVERTERS
EFFICIENCY
ELECTRICAL PROPERTIES
ELEMENTARY PARTICLES
ELEMENTS
EQUIPMENT
EVAPORATION
FERMIONS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
JUNCTIONS
LEPTONS
METALS
MICROSTRUCTURE
MOBILITY
PHASE TRANSFORMATIONS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
PHYSICAL PROPERTIES
PLATINUM METALS
SEMICONDUCTOR JUNCTIONS
SOLAR CELLS
SOLAR EQUIPMENT
TELLURIDES
TELLURIUM COMPOUNDS
TRANSITION ELEMENTS
SOLAR
CDTE
SINGLE-CRYSTAL
EVAPORATED
140501* - Solar Energy Conversion- Photovoltaic Conversion