Optical Absorption in Co-Deposited Mixed-Phase Hydrogenated Amorphous/Nanocrystalline Silicon Thin Films


The conductivity of amorphous/nanocrystalline hydrogenated silicon thin films (a/nc-Si:H) deposited in a dual chamber co-deposition system exhibits a non-monotonic dependence on the nanocrystal concentration. Optical absorption measurements derived from the constant photocurrent method (CPM) and preliminary electron spin resonance (ESR) data for similarly prepared materials are reported. The optical absorption spectra, in particular the subgap absorption, are found to be independent of nanocrystalline density for relatively small crystal fractions (< 4%). For films with a higher crystalline content, the absorption spectra indicate broader Urbach slopes and higher midgap absorption. The ESR spectra show an approximately constant defect density across all of the films. These data are interpreted in terms of a model involving electron donation from the nanocrystals into the amorphous material.

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  1. 1

    K. Yamamoto, IEEE Transactions on Electron Devices 46, 2041 (1999).

    CAS  Article  Google Scholar 

  2. 2

    B. Yan, G. Yue, J. M. Owens, J. Yang, and S. Guha, Appl. Phys. Lett. 85, 1925 (2004).

    CAS  Article  Google Scholar 

  3. 3

    M. L. Ostraat, J. W. D. Blauwe, M. L. Green, L. D. Bell, M. L. Brongersma, J. Casperson, R. C. Flagan, and H. A. Atwater, Appl. Phys. Lett. 79, 433 (2001).

    CAS  Article  Google Scholar 

  4. 4

    T. C. Chang, S. T. Yan, P. T. Liu, C. W. Chen, H. H. Wu, and S. M. Sze, Appl. Phys. Lett. 85, 248 (2004).

    CAS  Article  Google Scholar 

  5. 5

    N. Park, T. Kim, and S. Park, Appl. Phys. Lett. 78, 2575 (2001).

    CAS  Article  Google Scholar 

  6. 6

    D. L. Staebler and C. R. Wronski, Appl. Phys. Lett. 31, 292 (1977).

    CAS  Article  Google Scholar 

  7. 7

    D. L. Staebler and C. R. Wronski, J. Appl. Phys. 51, 3262 (1980).

    CAS  Article  Google Scholar 

  8. 8

    P. R. Cabarrocas, S. Hamma, P. St’ahel, C. Longeaud, J. P. Kleider, R. Meaudre, and M. Meaudre, in 14th European Photovoltaic Solar Energy Conference, Barcelona, Spain, edited by H. A. Ossenbrink, P. Helm and H. Ehmann (Bedford: H. S. Stephens & Associates, Bedford, 1997), p. 1444.

  9. 9

    Y. Adjallah, C. Anderson, U. Kortshagen, and J. Kakalios, J. Appl. Phys. 107, 043704 (2010).

    Article  Google Scholar 

  10. 10

    M. Vaněček, J. Kocka, J. Stuchlík, and A. Tríska, Solid State Commun. 39, 1199 (1981).

    Article  Google Scholar 

  11. 11

    W. B. Jackson, R. J. Nemanich, and N. M. Amer, Phys.Rev.B 27, 4861 (1983).

    Article  Google Scholar 

  12. 12

    N. Wyrsch, F. Finger, T. J. McMahon, and M. Vaněček, J. Non Cryst. Solids 137138, 347 (1991).

    Article  Google Scholar 

  13. 13

    W. B. Jackson, N. M. Amer, A. C. Boccara, and D. Fournier, Appl. Opt. 20, 1333 (1981).

    CAS  Article  Google Scholar 

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Wienkes, L.R., Besaws, A., Anderson, C. et al. Optical Absorption in Co-Deposited Mixed-Phase Hydrogenated Amorphous/Nanocrystalline Silicon Thin Films. MRS Online Proceedings Library 1245, 903 (2009). https://doi.org/10.1557/PROC-1245-A09-03

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