Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint

Dhere, R; Gessert, T; Zhou, J; Asher, S; Pankow, J; Moutinho, H

doi:10.1557/PROC-763-B8.25

Title: Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint

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Abstract

Modeling of two-junction tandem devices shows that for optimal device performance, the bandgap of the top cell should be around 1.6-1.8 eV. CdZnTe alloys can be tailored to yield bandgaps in the desired range. In this study, we considered were used to fabricate these films, using close-spaced sublimation (CSS) and radio-frequency sputtering (RFS) techniques. In the first approach, we used mixed powders of CdTe and ZnTe as the source for film deposition by CSS. Even for the ZnTe/CdTe (95:5 ratio) source material, the deposited films were entirely CdTe due to higher vapor pressure of CdTe. In the second approach, we used pre-alloyed CdZnTe powders (CERAC, Inc.) as the source. Due to the lower sticking coefficient of Zn, even for the source composition of 75% Zn, these films contained very low quantities of Zn (~5%). We tried unsuccessfully to increase the Zn content in the films by confining Zn vapor by enclosing the region between the source and substrate, reducing the substrate temperature to 400C, and adjusting the source/substance distance. Finally, we used thin-film couples consisting of 300-nm-thick CdTe deposited by CSS and 300-nm-thick ZnTe deposited by RFS; the samples were then heat-treated in cadmium chloride vapor. Compositional analysis of themore »« less

Authors:: Dhere, R; Gessert, T; Zhou, J; Asher, S; Pankow, J; Moutinho, H

Publication Date:: Tue Apr 01 00:00:00 EST 2003

Research Org.:: National Renewable Energy Lab. (NREL), Golden, CO (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 15004063

Report Number(s):: NREL/CP-520-33965
Journal ID: ISSN 1946--4274; TRN: US201015%%299

DOE Contract Number:: AC36-99-GO10337

Resource Type:: Conference

Resource Relation:: Journal Volume: 763; Conference: Prepared for the 2003 Materials Research Society Spring Meeting, 21-25 April 2003, San Francisco, California

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; ALLOYS; CADMIUM CHLORIDES; DEPOSITION; OXYGEN; PERFORMANCE; SIMULATION; SOLAR CELLS; SPUTTERING; SUBLIMATION; SUBSTRATES; VAPOR PRESSURE; PV; CDZNTE; TANDEM DEVICE; BANDGAP; CLOSE-SPACED SUBLIMATION (CSS); RADIO-FREQUENCY SPUTTERING (RFS); THIN-FILM; COUPLE; POST-DEPOSITION ANNEAL; INTERDIFFUSION; ATOMIC FORCE MICROSCOPY; X-RAY DIFFRACTION (XRD); AUGER ELECTRON SPECTROSCOPY (AES); SECONDARY ION MASS SPECTROMETRY (SIMS); Solar Energy - Photovoltaics

Citation Formats


                    Dhere, R, Gessert, T, Zhou, J, Asher, S, Pankow, J, and Moutinho, H. Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint.  United States: N. p., 2003. 
        Web.  doi:10.1557/PROC-763-B8.25.

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                    Dhere, R, Gessert, T, Zhou, J, Asher, S, Pankow, J, & Moutinho, H. Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint.  United States.  https://doi.org/10.1557/PROC-763-B8.25

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                    Dhere, R, Gessert, T, Zhou, J, Asher, S, Pankow, J, and Moutinho, H. 2003.  
        "Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint".  United States.  https://doi.org/10.1557/PROC-763-B8.25.  https://www.osti.gov/servlets/purl/15004063.

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@article{osti_15004063,

  title        = {Investigation of CdZnTe for Thin-Film Tandem Solar Cell Applications: Preprint},

  author       = {Dhere, R and Gessert, T and Zhou, J and Asher, S and Pankow, J and Moutinho, H},

  abstractNote = {Modeling of two-junction tandem devices shows that for optimal device performance, the bandgap of the top cell should be around 1.6-1.8 eV. CdZnTe alloys can be tailored to yield bandgaps in the desired range. In this study, we considered were used to fabricate these films, using close-spaced sublimation (CSS) and radio-frequency sputtering (RFS) techniques. In the first approach, we used mixed powders of CdTe and ZnTe as the source for film deposition by CSS. Even for the ZnTe/CdTe (95:5 ratio) source material, the deposited films were entirely CdTe due to higher vapor pressure of CdTe. In the second approach, we used pre-alloyed CdZnTe powders (CERAC, Inc.) as the source. Due to the lower sticking coefficient of Zn, even for the source composition of 75% Zn, these films contained very low quantities of Zn (~5%). We tried unsuccessfully to increase the Zn content in the films by confining Zn vapor by enclosing the region between the source and substrate, reducing the substrate temperature to 400C, and adjusting the source/substance distance. Finally, we used thin-film couples consisting of 300-nm-thick CdTe deposited by CSS and 300-nm-thick ZnTe deposited by RFS; the samples were then heat-treated in cadmium chloride vapor. Compositional analysis of the samples showed extensive interdiffusion of Cd and Zn for the annealed samples. We will present the data on the various stack configurations of CdTe and ZnTe, the effect of different post-deposition anneals, the effect of oxygen on the interdiffusion and alloy formation and its possible correlation to the device performance degradation.},

  doi          = {10.1557/PROC-763-B8.25},

  url          = {https://www.osti.gov/biblio/15004063},
  journal      = {},

  issn         = {1946--4274},

  number       = ,

  volume       = 763,

  place        = {United States},

  year         = {Tue Apr 01 00:00:00 EST 2003},

  month        = {Tue Apr 01 00:00:00 EST 2003}

}

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