Carrier Lifetime Measurements by Photoconductance at Low Temperature on Passivated Crystalline Silicon Wafers

Abstract

We propose an implementation of the PCD technique to minority carrier effective lifetime assessment in crystalline silicon at 77K. We focus here on (n)-type, FZ, polished wafers passivated by a-Si:H deposited by PECVD at 200°C. The samples were immersed into liquid N2 contained in a beaker placed on a Sinton lifetime tester. Prior to be converted into lifetimes, data were corrected for the height shift induced by the beaker. One issue lied in obtaining the sum of carrier mobilities at 77K. From dark conductance measurements performed on the lifetime tester, we extracted an electron mobility of 1.1x104 cm².V-1.s-1 at 77K, the doping density being independently calculated in order to account for the freezing effect of dopants. This way, we could obtain lifetime curves with respect to the carrier density. Effective lifetimes obtained at 77K proved to be significantly lower than at RT and not to depend upon the doping of the a-Si:H layers. We were also able to experimentally verify the expected rise in the implied Voc, which, on symmetrically passivated wafers, went up from 0.72V at RT to 1.04V at 77K under 1 sun equivalent illumination.

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References

  1. 1.

    S. De Wolf, A. Descoeudres, Z. C. Holman and C. Ballif, Green 2,7 (2012).

    Google Scholar 

  2. 2.

    R. Leadon and J. A. Naber, Journal of Applied Physics 40, 2633 (1969).

    CAS  Article  Google Scholar 

  3. 3.

    T. Trupke, J. Zhao, A. Wang, R. Corkish and M. A. Green, Applied Physics Letters 82, 2996 (2003).

    CAS  Article  Google Scholar 

  4. 4.

    S. Tardon, PhD. Thesis, Universität Oldenburg (2006).

  5. 5.

    S. De Wolf and M. Kondo, Journal of Applied Physics 105, 103707 (2009).

    Article  Google Scholar 

  6. 6.

    W. Favre, L. Bettaieb, J. Després, J. Alvarez, J.-P. Kleider, Y. Le Bihan, Z. Djebbour and D. Mencaraglia, Proceedings of the 26th EUPVSEC (2011).

  7. 7.

    B. Van Zeghbroeck, “Principles of Semiconductor Devices, 2.6.4.4”, Online http://ecee.colorado.edu/∼bart/book/welcome.htm (2011). [Accessed 19 March 2013].

  8. 8.

    S. S. Li and W. R. Thurder, Solid-State Electronic 20, 609 (1977).

    CAS  Article  Google Scholar 

  9. 9.

    H. Schlangenotto, H. Maeder and W. Gerlach, Phys. Status Solidi A 21, 357 (1974).

    CAS  Article  Google Scholar 

  10. 10.

    T. Trupke, M. A. Green, P. Würfel, P. P. Altermatt, A. Wang, J. Zhao and R. Corkish, Journal of Applied Physics 94, 4930 (2003).

    CAS  Article  Google Scholar 

  11. 11.

    P. P. Altermatt, J. Schmidt, G. Heiser and A. G. Aberle, Journal of Applied Physics 82, 4938 (1997).

    CAS  Article  Google Scholar 

  12. 12.

    A. Schenk, Solid-State Electronics 35, 1585 (1992).

    CAS  Article  Google Scholar 

  13. 13.

    S. M. Sze and K. K. Ng, Physics of Semiconductor Devices, 3 rd ed. (Wiley Intersciences, 2007) p18.

    Google Scholar 

Download references

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Correspondence to Guillaume Courtois.

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Courtois, G., Bruneau, B., Sobkowicz, I.P. et al. Carrier Lifetime Measurements by Photoconductance at Low Temperature on Passivated Crystalline Silicon Wafers. MRS Online Proceedings Library 1536, 119–125 (2013). https://doi.org/10.1557/opl.2013.600

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