Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics

Ablekim, Tursun; Perkins, Craig; Zheng, Xin; Reich, Carey; Swanson, Drew; Colegrove, Eric; Duenow, Joel N.; Albin, David; Nanayakkara, Sanjini; Reese, Matthew O.; Shimpi, Tushar; Sampath, Walajabad; Metzger, Wyatt K.

doi:10.1109/JPHOTOV.2018.2877982

Title: Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics

Abstract

Mg_xZn_1-xO (MZO) shows great promise to replace CdS as a buffer layer in CdTe-based solar cells. It is more transparent, and the MZO bandgap and electron density can be tuned, thus providing flexibility in controlling the conduction band offsets and recombination rates between transparent conductive oxide/MZO and MZO/CdSeTe interfaces. Integrating this material into solar cell devices has been frustrated by the common observation of abnormal current-voltage curves. Simulations indicate that this anomalous behavior can be attributed to front interface barrier effects. Experiments demonstrate that this common MZO interface problem can be resolved experimentally by surface preparation, preheat steps, and removing oxygen during absorber deposition and CdCl₂ treatment. Oxygen during the cell fabrication process is likely to alter MZO properties and MZO/CdSeTe band alignment. After addressing these interface issues and modest optimization, devices with high short-circuit density of 29 mA/cm² and efficiency above 16% are demonstrated.

Authors:

^[1];

^[1]; Zheng, Xin ^[1]; Reich, Carey ^[2]; Swanson, Drew ^[2];

^[1];

^[1]; Albin, David ^[1]; Nanayakkara, Sanjini ^[1];

^[1];

^[2]; Sampath, Walajabad ^[2]; Metzger, Wyatt K. ^[1]

National Renewable Energy Lab. (NREL), Golden, CO (United States)
Colorado State Univ., Fort Collins, CO (United States)

Publication Date:: Fri Feb 15 00:00:00 EST 2019

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

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office

OSTI Identifier:: 1514844

Report Number(s):: NREL/JA-5K00-72393
Journal ID: ISSN 2156-3381

Grant/Contract Number:: AC36-08GO28308

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Journal of Photovoltaics

Additional Journal Information:: Journal Volume: 9; Journal Issue: 3; Journal ID: ISSN 2156-3381

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; 36 MATERIALS SCIENCE; cadmium telluride; MgxZn1-xO; thin film solar cells; conduction band offset; interface

Citation Formats


                    Ablekim, Tursun, Perkins, Craig, Zheng, Xin, Reich, Carey, Swanson, Drew, Colegrove, Eric, Duenow, Joel N., Albin, David, Nanayakkara, Sanjini, Reese, Matthew O., Shimpi, Tushar, Sampath, Walajabad, and Metzger, Wyatt K. Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics.  United States: N. p., 2019. 
Web.  doi:10.1109/JPHOTOV.2018.2877982.

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                    Ablekim, Tursun, Perkins, Craig, Zheng, Xin, Reich, Carey, Swanson, Drew, Colegrove, Eric, Duenow, Joel N., Albin, David, Nanayakkara, Sanjini, Reese, Matthew O., Shimpi, Tushar, Sampath, Walajabad, & Metzger, Wyatt K. Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics.  United States.  https://doi.org/10.1109/JPHOTOV.2018.2877982

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                    Ablekim, Tursun, Perkins, Craig, Zheng, Xin, Reich, Carey, Swanson, Drew, Colegrove, Eric, Duenow, Joel N., Albin, David, Nanayakkara, Sanjini, Reese, Matthew O., Shimpi, Tushar, Sampath, Walajabad, and Metzger, Wyatt K. Fri .  
"Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics".  United States.  https://doi.org/10.1109/JPHOTOV.2018.2877982.  https://www.osti.gov/servlets/purl/1514844.

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@article{osti_1514844,

  title        = {Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics},

  author       = {Ablekim, Tursun and Perkins, Craig and Zheng, Xin and Reich, Carey and Swanson, Drew and Colegrove, Eric and Duenow, Joel N. and Albin, David and Nanayakkara, Sanjini and Reese, Matthew O. and Shimpi, Tushar and Sampath, Walajabad and Metzger, Wyatt K.},

  abstractNote = {MgxZn1-xO (MZO) shows great promise to replace CdS as a buffer layer in CdTe-based solar cells. It is more transparent, and the MZO bandgap and electron density can be tuned, thus providing flexibility in controlling the conduction band offsets and recombination rates between transparent conductive oxide/MZO and MZO/CdSeTe interfaces. Integrating this material into solar cell devices has been frustrated by the common observation of abnormal current-voltage curves. Simulations indicate that this anomalous behavior can be attributed to front interface barrier effects. Experiments demonstrate that this common MZO interface problem can be resolved experimentally by surface preparation, preheat steps, and removing oxygen during absorber deposition and CdCl2 treatment. Oxygen during the cell fabrication process is likely to alter MZO properties and MZO/CdSeTe band alignment. After addressing these interface issues and modest optimization, devices with high short-circuit density of 29 mA/cm2 and efficiency above 16% are demonstrated.},

  doi          = {10.1109/JPHOTOV.2018.2877982},

  journal      = {IEEE Journal of Photovoltaics},

  number       = 3,

  volume       = 9,

  place        = {United States},

  year         = {Fri Feb 15 00:00:00 EST 2019},

  month        = {Fri Feb 15 00:00:00 EST 2019}

}

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Works referencing / citing this record:

Recombination and bandgap engineering in CdSeTe/CdTe solar cells
journal, July 2019

Zheng, X.; Kuciauskas, D.; Moseley, J.
APL Materials, Vol. 7, Issue 7
DOI: 10.1063/1.5098459

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Title: Tailoring MgZnO/CdSeTe Interfaces for Photovoltaics

Abstract

Citation Formats

Recombination and bandgap engineering in CdSeTe/CdTe solar cells journal, July 2019

Recombination and bandgap engineering in CdSeTe/CdTe solar cells
journal, July 2019