Low-Cost CdZnTe Devices for Cascade Cell Application, Final Subcontract Report, 15 May 1989 - 15 May 1990

Technical Report · Thu Nov 01 00:00:00 EST 1990

DOI:https://doi.org/10.2172/6464070· OSTI ID:6464070

Basol, Bulent M.; Kapur, Vijay K.

This report describes a research program to develop a low-cost technique for producing Cd{sub 1-x}Zn{sub x}Te devices for cascade solar cell applications. The technique involves a two-stage process for fabricating such devices with a band gap of about 1.7 eV and a transparent contact layer of low-resistivity ZnTe. In the first stage, thin films of Cd, Zn, and Te are deposited in stacked layers as Cd{sub 1-x}An{sub x}Te. The second stage involves hearing and reacting the layers to form the compound. At first, electrodeposition was used for depositing the layers to successfully fabricate Dc{sub 1-x}Zn{sub x}Te thin-film devices. These films were also intrinsically doped with copper. For the first time, transparent ZnTe films of low resistivity were obtained in a two-stage process; preliminary solar cells using films with low Zn content were demonstrated. A second phase of the project involved growing films with higher Zn content (>15%). Such films were grown on CdS-coated substrates for fabricating devices. The effects of the solar-cell processing steps on the Cd{sub 1-x}Zn{sub x}Te and CdS/Cd{sub 1-x}Zn{sub x}Te interfaces were studied; results showed that the nature of the interface depended on the stoichiometry of the Cd{sub 1-x}Zn{sub x}Te thin film. A sharp interface was observed for the CdS/CdTe structures, but the interface became highly diffused as the Zn content in the absorber layer increased above 15%. The interaction between the CdS window layer and the Cd{sub 1-x}Zn{sub x}Te absorber layer was found to result from an exchange reaction between Zn in the absorber layer and the thin CdS film. 14 refs., 10 figs.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 6464070
• Report Number(s): SERI/TP-211-4033; ON: DE91002116
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140501* -- Solar Energy Conversion-- Photovoltaic Conversion
CADMIUM COMPOUNDS
CADMIUM SULFIDES
CADMIUM TELLURIDE SOLAR CELLS
CADMIUM TELLURIDES
cascade cells
CASCADE SOLAR CELLS
CHALCOGENIDES
COPPER
COST
CRYSTAL DOPING
DEPOSITION
DIRECT ENERGY CONVERTERS
DOCUMENT TYPES
ELECTRICAL PROPERTIES
ELECTRODEPOSITION
ELECTROLYSIS
ELEMENTS
EQUIPMENT
FABRICATION
FILMS
INORGANIC PHOSPHORS
INTERFACES
LYSIS
METALS
OPTICAL PROPERTIES
PHOSPHORS
PHOTOELECTRIC CELLS
PHOTOVOLTAIC CELLS
photovoltaics
PHYSICAL PROPERTIES
PROGRESS REPORT
RESEARCH PROGRAMS
SOLAR ABSORBERS
SOLAR CELLS
SOLAR EQUIPMENT
STOICHIOMETRY
SULFIDES
SULFUR COMPOUNDS
SURFACE COATING
TELLURIDES
TELLURIUM COMPOUNDS
THIN FILMS
TRANSITION ELEMENTS
ZINC COMPOUNDS
ZINC TELLURIDES