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Electronic structure and phase stability of In-free photovoltaic semiconductors, Cu2ZnSnSe4 and Cu2ZnSnS4 by first-principles calculation

Published online by Cambridge University Press:  31 January 2011

Tsuyoshi Maeda
Affiliation:
tmaeda@ad.ryukoku.ac.jp, Ryukoku University, Department of materials chemistry, Otsu, Shiga, Japan
Satoshi Nakamura
Affiliation:
t08m058@mail.ryukoku.ac.jp, Ryukoku University, Department of materials chemistry, Otsu, Shiga, Japan
Takahiro Wada
Affiliation:
twada@rins.ryukoku.ac.jp, Ryukoku University, Department of materials chemistry, Otsu, Japan
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Abstract

We have theoretically evaluated the phase stability and electronic structure of Cu2ZnSnSe4 (CZTSe) and Cu2ZnSnS4 (CZTS). The enthalpies of formation for kesterite, stannite and wurtz-stannite phases of CZTSe and CZTS were calculated using a plane-wave pseudopotential method within the density functional formalism. For CZTSe, the calculated formation enthalpy (ΔH) of the kesterite phase (−312.7 kJ/mol) is a little smaller than that of the stannite phase (−311.3 kJ/mol) and much smaller than that of the wurtz-stannite phase (−305.7 kJ/mol). For CZTS, the ΔH of the kesterite phase (−361.9 kJ/mol) is smaller than that of the stannite phase (−359.9 kJ/mol) and much smaller than that of the wurtz-stannite phase (−354.6 kJ/mol). The difference of ΔH between the kesterite and stannite phases for CZTS is greater than that for CZTSe. This indicates the kesterite phase is more stable than the stannite phase in CZTS compared with CZTSe. The valence band maximums (VBMs) of both the kesterite- and stannite-type CZTSe(CZTS) are antibonding orbitals of Cu 3d and Se 4p (S 3p). The conduction band minimums (CBMs) are antibonding orbitals of Sn 5s and Se 4p (S 3p). The Zn atom does not affect the VBM or the CBM in either CZTSe(CZTS). The theoretical band gap of the kesterite phase calculated with sX-LDA in both CZTSe and CZTS is a little wider than that of the wurtz-stannite phase and much wider than that of the stannite phase.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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References

1. Katagiri, H. Thin Solid Films 480-481 (2005) 426432.Google Scholar
2. Jaffe, J.E. and Zunger, Alex, Phys. Rev. B 28 5822 (1983).Google Scholar
3. Maeda, T. Takeichi, T. and Wada, T. phys. stat. sol. (a) 203, 2634(2006).Google Scholar
4. Nakamura, S. Maeda, T. and Wada, T. phys. stat. sol. (c). in press.Google Scholar
5. Perdew, J. P. Chevary, J. A. Jackson, K. A. Pederson, M. R. Singh, D. J. Vosko, S. H. Fiolhais, C. Phys. Rev. B 46, 6671(1992).Google Scholar
6. Milman, V. Winkler, B. White, J. A. Pickard, C. J. Payne, M. C. Akhmatskaya, E. V. and Nobes, R. H. Int. J. Quantum Chem. 77, 895(2000).Google Scholar
7. Vanderbilt, D. Phys. Rev. B 41, 7892(1990).Google Scholar
8. Monkhorst, H. J. and Pack, J. D. Phys. Rev. B 13, 1588(1976).Google Scholar
9. Kresse, G. Furthmüller, J., Phys. Rev. B 54, 11169(1996).Google Scholar
10. Payne, M. C. Teter, M. P. Allan, D. C. Arias, T. A. Joannopoulos, J. D. Rev. Mod. Phys. 64, 1045(1992).Google Scholar
11. Press, W. H. Teukolsky, S. A. Vetterling, W. T. and Flannery, B. P. Numerical Recipes (Cambridge University Press, Cambridge, 1992) 2nd ed., p.418.Google Scholar
12. Shigemi, A. and Wada, T. Jpn. J. Appl. Phys. 44, 8048(2005).Google Scholar
13. Maeda, T. and Wada, T. phys. stat. sol. (c), in press.Google Scholar
14. Chen, S. Gong, X. G. Walsh, A. and Wei, S. H. Appl. Phys. Lett. 94, 041903(2009).Google Scholar