Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques

Garris, Rebekah L.; Johnston, Steven; Li, Jian V.; Guthrey, Harvey L.; Ramanathan, Kannan; Mansfield, Lorelle M.

doi:10.1016/j.solmat.2017.08.027

Title: Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques

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Abstract

In a previous study, we reported on Cu(In,Ga)Se2-based (CIGS) solar cell samples collected from different research laboratories and industrial companies with the purpose of understanding the range of CIGS materials that can lead to high-quality and high-efficiency solar panels. Here, we report on electrical measurements of those same samples. Electron-beam induced current and time-resolved photoluminescence (TRPL) gave insights about the collection probability and the lifetime of carriers generated in each absorber. Capacitance and drive-level capacitance profiling revealed nonuniformity in carrier-density profiles. Admittance spectroscopy revealed small activation energies (= 0.03 eV) indicative of the inversion strength, larger activation energies (> 0.1 eV) reflective of thermal activation of absorber conductivity and a deeper defect level. Deep-level transient spectroscopy (DLTS) probed deep hole-trapping defects and showed that all samples in this study had a majority-carrier defect with activation energy between 0.3 eV and 0.9 eV. Optical-DLTS revealed deep electron-trapping defects in several of the CIGS samples. This work focused on revealing similarities and differences between high-quality CIGS solar cells made with various structures and fabrication techniques.

Authors:

Garris, Rebekah L. ^[1]; Johnston, Steven ^[1]; Li, Jian V. ^[1]; Guthrey, Harvey L. ^[1]; Ramanathan, Kannan ^[1];

^[1]

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

Publication Date:: Thu Aug 31 00:00:00 EDT 2017

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:: 1389740

Alternate Identifier(s):: OSTI ID: 1549915

Report Number(s):: NREL/JA-5K00-67143
Journal ID: ISSN 0927-0248

Grant/Contract Number:: AC36-08GO28308

Resource Type:: Accepted Manuscript

Journal Name:: Solar Energy Materials and Solar Cells

Additional Journal Information:: Journal Volume: 174; Journal Issue: C; Journal ID: ISSN 0927-0248

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; admittance spectroscopy; capacitance; cross-sectional electron-beam induced current (EBIC); Cu(In,Ga)Se2 (CIGS); deep-level transient spectroscopy (DLTS); drive-level capacitance profiling (DLCP); electrical characterization; optical-DLTS; thin-film photovoltaics; time-resolved photoluminescence (TRPL); two-photon excitation

Citation Formats


                    Garris, Rebekah L., Johnston, Steven, Li, Jian V., Guthrey, Harvey L., Ramanathan, Kannan, and Mansfield, Lorelle M. Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques.  United States: N. p., 2017. 
Web.  doi:10.1016/j.solmat.2017.08.027.

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                    Garris, Rebekah L., Johnston, Steven, Li, Jian V., Guthrey, Harvey L., Ramanathan, Kannan, & Mansfield, Lorelle M. Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques.  United States.  https://doi.org/10.1016/j.solmat.2017.08.027

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                    Garris, Rebekah L., Johnston, Steven, Li, Jian V., Guthrey, Harvey L., Ramanathan, Kannan, and Mansfield, Lorelle M. Thu .  
"Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques".  United States.  https://doi.org/10.1016/j.solmat.2017.08.027.  https://www.osti.gov/servlets/purl/1389740.

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@article{osti_1389740,

  title        = {Electrical characterization and comparison of CIGS solar cells made with different structures and fabrication techniques},

  author       = {Garris, Rebekah L. and Johnston, Steven and Li, Jian V. and Guthrey, Harvey L. and Ramanathan, Kannan and Mansfield, Lorelle M.},

  abstractNote = {In a previous study, we reported on Cu(In,Ga)Se2-based (CIGS) solar cell samples collected from different research laboratories and industrial companies with the purpose of understanding the range of CIGS materials that can lead to high-quality and high-efficiency solar panels. Here, we report on electrical measurements of those same samples. Electron-beam induced current and time-resolved photoluminescence (TRPL) gave insights about the collection probability and the lifetime of carriers generated in each absorber. Capacitance and drive-level capacitance profiling revealed nonuniformity in carrier-density profiles. Admittance spectroscopy revealed small activation energies (= 0.03 eV) indicative of the inversion strength, larger activation energies (> 0.1 eV) reflective of thermal activation of absorber conductivity and a deeper defect level. Deep-level transient spectroscopy (DLTS) probed deep hole-trapping defects and showed that all samples in this study had a majority-carrier defect with activation energy between 0.3 eV and 0.9 eV. Optical-DLTS revealed deep electron-trapping defects in several of the CIGS samples. This work focused on revealing similarities and differences between high-quality CIGS solar cells made with various structures and fabrication techniques.},

  doi          = {10.1016/j.solmat.2017.08.027},

  journal      = {Solar Energy Materials and Solar Cells},

  number       = C,

  volume       = 174,

  place        = {United States},

  year         = {Thu Aug 31 00:00:00 EDT 2017},

  month        = {Thu Aug 31 00:00:00 EDT 2017}

}

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