Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells

doi:10.1021/acsaem.9b01771

Title: Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells

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Abstract

Hydrogen-assisted defect engineering, via a hydrogenated silicon nitride (SiN_x:H) capping layer, on doped polycrystalline silicon (poly-Si) passivating-contact structures, is explored using complementary techniques. The hydrogen treatment universally improves the passivation quality of poly-Si/SiO_x stacks on all samples investigated. Meanwhile, their contact resistivity remains very low at ~6 m$$\Omega$$cm². Moreover, the nature of charge carrier recombination within the poly-Si films is also investigated by means of photoluminescence. On planar c-Si substrates, the poly-Si films emit two broad photoluminescence peaks ~850-1050 nm and ~1300-1500 nm. The former is the characteristic peak of the hydrogenated amorphous Si (a-Si:H) phase and only appears after the treatment, demonstrating that i) a significant amount of hydrogen has been driven into the poly-Si film and ii) an amorphous phase is present within it. The second peak originates from sub-bandgap radiative defects inside the poly-Si films and increases after the treatment, suggesting a suppression of their non-radiative recombination channels. For films deposited on textured c-Si substrates, there is a disrupted oxide boundary, preventing a build-up of excess carriers inside the films and leading to quenching of the film luminescence.

Authors:

^[1]; Yan, Di ^[1]; Samundsett, Christian ^[1];

^[1];

^[2]; Young, Matthew ^[2]; Ding, Zetao ^[1];

^[1]; Kremer, Felipe ^[1]; Al-Jassim, Mowafak ^[2]; Cuevas, Andres ^[1]; Macdonald, Daniel ^[1];

^[1]

Australian National Univ., Canberra, ACT (Australia)
National Renewable Energy Lab. (NREL), Golden, CO (United States)

Publication Date:: 2019-11-26

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; Australian Renewable Energy Agency (ARENA); Australian Centre for Advanced Photovoltaics (ACAP); Australian Government Research Training Program (RTP)

OSTI Identifier:: 1579320

Report Number(s):: NREL/JA-5K00-74683
Journal ID: ISSN 2574-0962

Grant/Contract Number:: AC36-08GO28308; RND017

Resource Type:: Accepted Manuscript

Journal Name:: ACS Applied Energy Materials

Additional Journal Information:: Journal Volume: 2; Journal Issue: 12; Journal ID: ISSN 2574-0962

Publisher:: American Chemical Society (ACS)

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; hydrogenation; doped polycrystalline silicon; amorphous silicon; passivating contacts; photoluminescence

Citation Formats


                    Truong, Thien N., Yan, Di, Samundsett, Christian, Liu, Anyao, Harvey, Steven P., Young, Matthew, Ding, Zetao, Tebyetekerwa, Mike, Kremer, Felipe, Al-Jassim, Mowafak, Cuevas, Andres, Macdonald, Daniel, and Nguyen, Hieu T. Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells.  United States: N. p., 2019. 
        Web.  doi:10.1021/acsaem.9b01771.

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                    Truong, Thien N., Yan, Di, Samundsett, Christian, Liu, Anyao, Harvey, Steven P., Young, Matthew, Ding, Zetao, Tebyetekerwa, Mike, Kremer, Felipe, Al-Jassim, Mowafak, Cuevas, Andres, Macdonald, Daniel, & Nguyen, Hieu T. Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells.  United States.  doi:10.1021/acsaem.9b01771.

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                    Truong, Thien N., Yan, Di, Samundsett, Christian, Liu, Anyao, Harvey, Steven P., Young, Matthew, Ding, Zetao, Tebyetekerwa, Mike, Kremer, Felipe, Al-Jassim, Mowafak, Cuevas, Andres, Macdonald, Daniel, and Nguyen, Hieu T. Tue .  
        "Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells".  United States.  doi:10.1021/acsaem.9b01771.  https://www.osti.gov/servlets/purl/1579320.

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@article{osti_1579320,

  title        = {Hydrogen-Assisted Defect Engineering of Doped Poly-Si Films for Passivating Contact Solar Cells},

  author       = {Truong, Thien N. and Yan, Di and Samundsett, Christian and Liu, Anyao and Harvey, Steven P. and Young, Matthew and Ding, Zetao and Tebyetekerwa, Mike and Kremer, Felipe and Al-Jassim, Mowafak and Cuevas, Andres and Macdonald, Daniel and Nguyen, Hieu T.},

  abstractNote = {Hydrogen-assisted defect engineering, via a hydrogenated silicon nitride (SiNx:H) capping layer, on doped polycrystalline silicon (poly-Si) passivating-contact structures, is explored using complementary techniques. The hydrogen treatment universally improves the passivation quality of poly-Si/SiOx stacks on all samples investigated. Meanwhile, their contact resistivity remains very low at ~6 m$\Omega$cm2. Moreover, the nature of charge carrier recombination within the poly-Si films is also investigated by means of photoluminescence. On planar c-Si substrates, the poly-Si films emit two broad photoluminescence peaks ~850-1050 nm and ~1300-1500 nm. The former is the characteristic peak of the hydrogenated amorphous Si (a-Si:H) phase and only appears after the treatment, demonstrating that i) a significant amount of hydrogen has been driven into the poly-Si film and ii) an amorphous phase is present within it. The second peak originates from sub-bandgap radiative defects inside the poly-Si films and increases after the treatment, suggesting a suppression of their non-radiative recombination channels. For films deposited on textured c-Si substrates, there is a disrupted oxide boundary, preventing a build-up of excess carriers inside the films and leading to quenching of the film luminescence.},

  doi          = {10.1021/acsaem.9b01771},

  journal      = {ACS Applied Energy Materials},

  number       = 12,

  volume       = 2,

  place        = {United States},

  year         = {2019},

  month        = {11}

}

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DOI: 10.1021/acsaem.9b01771

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