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Promotion of boron diffusion and gettering by employing thin Al2O3 layer as a reaction barrier

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Abstract

The formation of a boron-rich layer (BRL) is a common phenomenon during the fabrication of boron (B) emitter due to different solubility of B in the silicon oxide layer and the silicon substrate. In our work, we employ alumina oxide (Al2O3) layers as reaction barriers to avoid the production of the silicon oxide layer and eliminate the BRL. The B diffusion in silicon becomes much more accessible that the diffusion concentration and depth are increased dramatically with the absence of BRL. The Al2O3 layer can also improve the uniformity of surface sheet resistance due to its hydrophilic, bringing superior quality of liquid boron source spin coating. We investigate the influence of Al2O3 with different thicknesses and refractive indexes on the B diffusion. The diffusion profiles of B in the silicon capped with Al2O3 become broader as the thicknesses and refractive indexes of Al2O3 increase. Besides, iron is employed as a model impurity to study the gettering effects during the B diffusion. The increase of the maximum B concentration and the total amount of B doping contribute to a superior gettering effect with the interstitial iron concentration decrease from 3.91e12 cm−3 to a minimal value of 1.65e11 cm−3, and the iron concentration even dropped to 7.24e10 cm−3 after attaching a second deposition. We analyze the mechanisms of gettering systematically during the B diffusion. The present work will help deepen the understanding of B doping and the fabrication of B emitter.

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References

  1. S.P. Phang, W. Liang, B. Wolpensinger, M.A. Kessler, D. Macdonald, Tradeoffs between impurity gettering, bulk degradation, and surface passivation of boron-rich layers on silicon solar cells. IEEE J. Photovolt. 3, 261–266 (2013)

    Article  Google Scholar 

  2. H.C. Sio, D. Macdonald, Direct comparison of the electrical properties of multicrystalline silicon materials for solar cells: conventional p-type, n-type and high performance p-type. Sol. Energy Mater. Sol. Cells 144, 339–346 (2016)

    Article  CAS  Google Scholar 

  3. B. Singha, C.S. Solanki, Boron-rich layer properties formed by boron spin on dopant diffusion in n -type silicon. Mater. Sci. Semicond. Process. 57, 83–89 (2017)

    Article  CAS  Google Scholar 

  4. B. Singha, C.S. Solanki, Impact of a boron rich layer on minority carrier lifetime degradation in boron spin-on dopant diffused n-type crystalline silicon solar cells. Semicond. Sci. Technol. 31, 035009 (2016)

    Article  Google Scholar 

  5. N. Yang, S. Li, J. Yang, H. Li, X. Ye, C. Liu, X. Yuan, Avoidance of boron rich layer formation in the industrial boron spin-on dopant diffused n-type silicon solar cell without additional oxidation process. J. Mater. Sci.: Mater. Electron. 29, 20081–20086 (2018)

    CAS  Google Scholar 

  6. J. Schön, F. Schindler, W. Kwapil, M. Knörlein, P. Krenckel, S. Riepe, W. Warta, M.C. Schubert, Identification of the most relevant metal impurities in mc n-type silicon for solar cells. Sol. Energy Mater. Sol. Cells 142, 107–115 (2015)

    Article  Google Scholar 

  7. A. Hajjiah, M. Soha, I. Gordon, J. Poortmans, J. John, The impact of interstitial Fe contamination on n-type Cz-silicon for high efficiency solar cells. Solar Energy Mater. Solar Cells 211, 11050 (2020)

    Article  Google Scholar 

  8. D.H. Macdonald, L.J. Geerligs, A. Azzizi, Iron detection in crystalline silicon by carrier lifetime measurements for arbitrary injection and doping. J. Appl. Phys. 95, 1021–1028 (2004)

    Article  CAS  Google Scholar 

  9. A. Liu, D. Yan, S.P. Phang, A. Cuevas, D. Macdonald, Effective impurity gettering by phosphorus and boron-diffused polysilicon passivating contacts for silicon solar cells. Sol. Energy Mater. Sol. Cells 179, 136–141 (2018)

    Article  CAS  Google Scholar 

  10. P.A. Stolk, J.L. Benton, D.J. Eaglesham, D.C. Jacobson, J.Y. Cheng, J.M. Poate, S.M. Myers, T.E. Haynes, The mechanism of iron gettering in boron-doped silicon. Appl. Phys. Lett. 68, 51–53 (1996)

    Article  CAS  Google Scholar 

  11. E. Lohmüller, S. Lohmüller, N. Wöhrle, U. Belledin, A. Wolf, BBr3 diffusion with second deposition for laser-doped selective emitters from borosilicate glass. Sol. Energy Mater. Sol. Cells 186, 291–299 (2018)

    Article  Google Scholar 

  12. S.M. Myers, G.A. Petersen, T.J. Headley, J.R. Michael, T.L. Aselage, C.H. Seager, Metal gettering by boron-silicide precipitates in boron-implanted silicon. Nucl. Instrum. Methods Phys. Res. B 128, 291–296 (1997)

    Article  Google Scholar 

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Funding

This work was supported by the National Key R&D Program of China (2018YFB1500300).

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Authors and Affiliations

  1. School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, 200237, China

    Zhen Zhang, Minglei Lu, Xiao Yuan, Xiaojun Ye, Cui Liu & Hongbo Li

  2. Shanghai Institute of Space Power-Sources, China Aerospace Science and Technology Corporation, Shanghai, 200245, China

    Ning Yang

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  1. Zhen Zhang
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  3. Minglei Lu
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  7. Hongbo Li
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Correspondence to Cui Liu or Hongbo Li.

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Zhang, Z., Yang, N., Lu, M. et al. Promotion of boron diffusion and gettering by employing thin Al2O3 layer as a reaction barrier. J Mater Sci: Mater Electron 32, 8205–8212 (2021). https://doi.org/10.1007/s10854-020-05124-6

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  • DOI: https://doi.org/10.1007/s10854-020-05124-6

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