Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs

Schulte, Kevin L.; France, Ryan M.; Geisz, John F.

doi:10.1109/JPHOTOV.2016.2619183

Title: Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs

Abstract

The development of compositionally graded buffer layers (CGBs) with enhanced transparency would enable novel five and six junction solar cells, with efficiencies approaching 50% under high concentration. Here, we demonstrate highly transparent grades between the GaAs and InP lattice constants on both A- and B-miscut GaAs substrates, employing Al_xGayIn_1-x-yAs and highly Se-doped Burstein-Moss (BM) shifted Ga_xIn _1-xP. Transparency to >810 and >890 nm wavelengths is demonstrated with BM-shifted Ga_xIn_1-xP on B-miscut substrates and Al_xGayIn_1-x-yAs/Ga_xIn_1-xP(Se) combined grades on A-miscut substrates, respectively. 0.74 eV GaInAs solar cells grown on these transparent CGBs exhibit Woc = 0.41 V at mA/ cm², performance comparable with the state-of-the-art Ga_xIn_1-xP grade employed in the four-junction-inverted metamorphic multijunction (IMM) cell. A GaAs/0.74cV GaInAs tandem cell was grown with a transparent BM-shifted Ga_xIn_1-xP CGB to verify the CGB performance in a multijunction device structure. Quantum efficiency measurements indicate that the CGB is completely transparent to photons below the GaAs bandedge, validating its use in 4-6 junction IMM devices with a single-graded buffer. Furthermore, this tandem represents a highly efficient two-junction band gap combination, achieving 29.6% ± 1.2% efficiency under the AM1.5 global spectrum, demonstrating how the additional transparency enables new device structures.

Authors:

Schulte, Kevin L. ^[1]; France, Ryan M. ^[1]; Geisz, John F. ^[1]

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

Publication Date:: Fri Nov 11 00:00:00 EST 2016

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:: 1342505

Report Number(s):: NREL/JA-5J00-66503
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: 7; Journal Issue: 1; Journal ID: ISSN 2156-3381

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; photovoltaic cells; III-V semiconductor materials; semiconductor epitaxial layers; semiconductor device doping

Citation Formats


                    Schulte, Kevin L., France, Ryan M., and Geisz, John F. Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs.  United States: N. p., 2016. 
Web.  doi:10.1109/JPHOTOV.2016.2619183.

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                    Schulte, Kevin L., France, Ryan M., & Geisz, John F. Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs.  United States.  https://doi.org/10.1109/JPHOTOV.2016.2619183

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                    Schulte, Kevin L., France, Ryan M., and Geisz, John F. Fri .  
"Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs".  United States.  https://doi.org/10.1109/JPHOTOV.2016.2619183.  https://www.osti.gov/servlets/purl/1342505.

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@article{osti_1342505,

  title        = {Highly Transparent Compositionally Graded Buffers for New Metamorphic Multijunction Solar Cell Designs},

  author       = {Schulte, Kevin L. and France, Ryan M. and Geisz, John F.},

  abstractNote = {The development of compositionally graded buffer layers (CGBs) with enhanced transparency would enable novel five and six junction solar cells, with efficiencies approaching 50% under high concentration. Here, we demonstrate highly transparent grades between the GaAs and InP lattice constants on both A- and B-miscut GaAs substrates, employing AlxGayIn1-x-yAs and highly Se-doped Burstein-Moss (BM) shifted GaxIn 1-xP. Transparency to >810 and >890 nm wavelengths is demonstrated with BM-shifted GaxIn1-xP on B-miscut substrates and AlxGayIn1-x-yAs/GaxIn1-xP(Se) combined grades on A-miscut substrates, respectively. 0.74 eV GaInAs solar cells grown on these transparent CGBs exhibit Woc = 0.41 V at mA/ cm2, performance comparable with the state-of-the-art GaxIn1-xP grade employed in the four-junction-inverted metamorphic multijunction (IMM) cell. A GaAs/0.74cV GaInAs tandem cell was grown with a transparent BM-shifted GaxIn1-xP CGB to verify the CGB performance in a multijunction device structure. Quantum efficiency measurements indicate that the CGB is completely transparent to photons below the GaAs bandedge, validating its use in 4-6 junction IMM devices with a single-graded buffer. Furthermore, this tandem represents a highly efficient two-junction band gap combination, achieving 29.6% ± 1.2% efficiency under the AM1.5 global spectrum, demonstrating how the additional transparency enables new device structures.},

  doi          = {10.1109/JPHOTOV.2016.2619183},

  journal      = {IEEE Journal of Photovoltaics},

  number       = 1,

  volume       = 7,

  place        = {United States},

  year         = {Fri Nov 11 00:00:00 EST 2016},

  month        = {Fri Nov 11 00:00:00 EST 2016}

}

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Works referencing / citing this record:

Pathway to 50% efficient inverted metamorphic concentrator solar cells
conference, January 2017

Geisz, John F.; Steiner, Myles A.; Jain, Nikhil
13TH INTERNATIONAL CONFERENCE ON CONCENTRATOR PHOTOVOLTAIC SYSTEMS (CPV-13), AIP Conference Proceedings
DOI: 10.1063/1.5001425

High-efficiency inverted metamorphic 1.7/1.1 eV GaInAsP/GaInAs dual-junction solar cells
journal, January 2018

Jain, Nikhil; Schulte, Kevin L.; Geisz, John F.
Applied Physics Letters, Vol. 112, Issue 5
DOI: 10.1063/1.5008517

Six-junction concentrator solar cells
conference, January 2018

Geisz, John F.; Steiner, Myles A.; Schulte, Kevin L.
14TH INTERNATIONAL CONFERENCE ON CONCENTRATOR PHOTOVOLTAIC SYSTEMS (CPV-14), AIP Conference Proceedings
DOI: 10.1063/1.5053512

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