Calculation of Defect Concentrations and Phase Stability in Cu$_2$ ZnSnS$_4$ and Cu$_2$ ZnSnSe$_4$ From Stoichiometry

Mutter, Daniel; Dunham, Scott T.

doi:10.1109/JPHOTOV.2015.2430015

Title: Calculation of Defect Concentrations and Phase Stability in Cu$$_2$$ ZnSnS$$_4$$ and Cu$$_2$$ ZnSnSe$$_4$$ From Stoichiometry

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Abstract

The application of the quarternary compounds Cu$$_2$$ ZnSnS$$_4$$(CZTS) and Cu$$_2$$ ZnSnSe$$_4$$(CZTSe) as efficient solar cell absorber materials is dependent on the complex behavior of the large variety of intrinsic lattice defects. In this paper, a canonical approach is presented and applied to calculate the defect concentrations and the position of the Fermi level for CZTS and CZTSe at a given temperature as a function of stoichiometry (or a combination of stoichiometry and elemental chemical potentials). With the defect concentrations, the chemical potentials (which are generally not experimentally accessible) can be calculated, allowing the relation of sample composition to the phase stability of CZTS and CZTSe with respect to secondary compounds. Based on the model, it is shown that the stable CZTS with off-stoichiometric composition requires both Cu-poor and Zn-rich conditions, while the compositional space corresponding to stable CZTSe is wider than for CZTS. Additionally, the determination of the Fermi level directly relates the desired p-type conductivity to phase stability in both materials. The method used in this study is applicable to a wide range of complex materials.

Authors:

Mutter, Daniel ^[1]; Dunham, Scott T. ^[1]

Univ. of Washington, Seattle, WA (United States). Dept. of Electrical Engineering

Publication Date:: Wed Jul 01 00:00:00 EDT 2015

Research Org.:: Stanford Univ., CA (United States); Univ. of Washington, Seattle, WA (United States)

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

OSTI Identifier:: 1579860

Grant/Contract Number:: EE0004946

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Journal of Photovoltaics

Additional Journal Information:: Journal Volume: 5; Journal Issue: 4; Journal ID: ISSN 2156-3381

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 14 SOLAR ENERGY; 36 MATERIALS SCIENCE

Citation Formats


                    Mutter, Daniel, and Dunham, Scott T. Calculation of Defect Concentrations and Phase Stability in Cu$_2$ ZnSnS$_4$ and Cu$_2$ ZnSnSe$_4$ From Stoichiometry.  United States: N. p., 2015. 
Web.  doi:10.1109/JPHOTOV.2015.2430015.

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                    Mutter, Daniel, & Dunham, Scott T. Calculation of Defect Concentrations and Phase Stability in Cu$_2$ ZnSnS$_4$ and Cu$_2$ ZnSnSe$_4$ From Stoichiometry.  United States.  https://doi.org/10.1109/JPHOTOV.2015.2430015

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                    Mutter, Daniel, and Dunham, Scott T. Wed .  
"Calculation of Defect Concentrations and Phase Stability in Cu$_2$ ZnSnS$_4$ and Cu$_2$ ZnSnSe$_4$ From Stoichiometry".  United States.  https://doi.org/10.1109/JPHOTOV.2015.2430015.  https://www.osti.gov/servlets/purl/1579860.

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@article{osti_1579860,

  title        = {Calculation of Defect Concentrations and Phase Stability in Cu$_2$ ZnSnS$_4$ and Cu$_2$ ZnSnSe$_4$ From Stoichiometry},

  author       = {Mutter, Daniel and Dunham, Scott T.},

  abstractNote = {The application of the quarternary compounds Cu$_2$ ZnSnS$_4$(CZTS) and Cu$_2$ ZnSnSe$_4$(CZTSe) as efficient solar cell absorber materials is dependent on the complex behavior of the large variety of intrinsic lattice defects. In this paper, a canonical approach is presented and applied to calculate the defect concentrations and the position of the Fermi level for CZTS and CZTSe at a given temperature as a function of stoichiometry (or a combination of stoichiometry and elemental chemical potentials). With the defect concentrations, the chemical potentials (which are generally not experimentally accessible) can be calculated, allowing the relation of sample composition to the phase stability of CZTS and CZTSe with respect to secondary compounds. Based on the model, it is shown that the stable CZTS with off-stoichiometric composition requires both Cu-poor and Zn-rich conditions, while the compositional space corresponding to stable CZTSe is wider than for CZTS. Additionally, the determination of the Fermi level directly relates the desired p-type conductivity to phase stability in both materials. The method used in this study is applicable to a wide range of complex materials.},

  doi          = {10.1109/JPHOTOV.2015.2430015},

  journal      = {IEEE Journal of Photovoltaics},

  number       = 4,

  volume       = 5,

  place        = {United States},

  year         = {Wed Jul 01 00:00:00 EDT 2015},

  month        = {Wed Jul 01 00:00:00 EDT 2015}

}

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