Frontiers of Optoelectronics

, Volume 10, Issue 1, pp 31–37 | Cite as

Structural, optical and electrical properties of ZnO: B thin films with different thickness for bifacial a-Si:H/c-Si heterojunction solar cells

  • Dong Xu
  • Sheng Yin
  • Xiangbin Zeng
  • Song Yang
  • Xixing Wen
Research Article
  • 60 Downloads

Abstract

Textured surface boron-doped zinc oxide (BZO) thin films were fabricated by metal organic chemical vapor deposition as transparent conductive oxide (TCO) for solar cells. The surface microstructure was characterized by X-ray diffraction spectrum and scanning electron microscope. The optical transmittance was shown by optical transmittance microscope and the electrical properties were tested by Hall measurements. The thickness of the BZO film has crucial impact on the surface morphology, optical transmittance, and resistivity. The electrical and optical properties as well as surface microstructure varied inconsistently with the increase of the film thickness. The grain size and the surface roughness increased with the increase of the film thickness. The conductivity increased from 0.96×103 to 6.94×103 S/cm while the optical transmittance decreased from above 85% to nearly 80% with the increase of film thickness from 195 to 1021 nm. The BZO films deposited as both front and back transparent electrodes were applied to the bifacial ptype a-Si:H/i-type a-Si:H/n-type c-Si/i-type a-Si:H/n+-type a-Si:H heterojunction solar cells to obtain the optimized parameter of thickness. The highest efficiency of all the samples was 17.8% obtained with the BZO film thickness of 829 nm. Meanwhile, the fill factor was 0.676, the opencircuit voltage was 0.63 Vand the short-circuit density was 41.79 mA/cm2. The properties of the solar cells changing with the thickness were also investigated.

Keywords

boron-doped zinc oxide (BZO) metal organic chemical vapor deposition (MOCVD) heterojunction solar cell thickness textured surface transparent conductive oxide (TCO) 

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Notes

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 51472096) and the Supporting Technology Project of Education of China (No. 62501040202). The authors would like to thank all members of the thin film group at the Photonic and Information System Integration Institute for their support of this work and helpful discussion. The authors also thank Analytical and Testing Center of Huazhong University of Science & Technology for SEM measurement and Optoelectronic Micro/nano Fabrication Faculty of Wuhan National Laboratory for XRD and optical measurements and analysis of samples for their valuable suggestions and help for the samples characterizations

References

  1. 1.
    Wenas W W, Yamada A, Takahashi K, Yoshino M, Konagai M Electrical and optical properties of boron-doped ZnO thin films for solar cells grown by metalorganic chemical vapor deposition. Journal of Applied Physics, 1991, 70(11): 7119–7123CrossRefGoogle Scholar
  2. 2.
    Choi I. Properties of boron-doped ZnO thin films grown by using MOCVD. Journal of the Korean Physical Society, 2013, 63(10): 1997–2001CrossRefGoogle Scholar
  3. 3.
    Gao L, Zhang Y, Zhang J, Xu K. Boron doped ZnO thin films fabricated by RF-magnetron sputtering. Applied Surface Science, 2011, 257(7): 2498–2502CrossRefGoogle Scholar
  4. 4.
    Jana S, Vuk A S, Mallick A, Orel B, Biswas P K. Effect of boron doping on optical properties of sol-gel based nanostructured zinc oxide films on glass. Materials Research Bulletin, 2011, 46(12): 2392–2397CrossRefGoogle Scholar
  5. 5.
    Pawar B N, Jadkar S R, Takwale M G. Deposition and characterization of transparent and conductive sprayed ZnO:B thin films. Journal of Physics and Chemistry of Solids, 2005, 66(10): 1779–1782CrossRefGoogle Scholar
  6. 6.
    Yamamoto Y, Saito K, Takahashi K, Konagai M. Preparation of boron-doped ZnO thin films by photo-atomic layer deposition. Solar Energy Materials and Solar Cells, 2001, 65(1-4): 125–132CrossRefGoogle Scholar
  7. 7.
    Müller J, Rech B, Springer J, Vanecek M. TCO and light trapping in silicon thin film solar cells. Solar Energy, 2004, 77(6): 917–930CrossRefGoogle Scholar
  8. 8.
    Yin J, Zhu H, Wang Y, Wang Z, Gao J, Mai Y, Ma Y, Wan M, Huang Y. A study of ZnO:B films for thin film silicon solar cells. Applied Surface Science, 2012, 259:758–763CrossRefGoogle Scholar
  9. 9.
    Zeng X, Wen X, Sun X, Liao W, Wen Y. Boron-doped zinc oxide thin films grown by metal organic chemical vapor deposition for bifacial a-Si:H/c-Si heterojunction solar cells. Thin Solid Films, 2016, 605(30): 257–262CrossRefGoogle Scholar
  10. 10.
    Addonizio M L, Diletto C. Doping influence on intrinsic stress and carrier mobility of LP-MOCVD-deposited ZnO:B thin films. Solar Energy Materials and Solar Cells, 2008, 92(11): 1488–1494CrossRefGoogle Scholar
  11. 11.
    Dong B, Fang G, Wang J, Guan W, Zhao X. Effect of thickness on structural, electrical, and optical properties of ZnO: Al films deposited by pulsed laser deposition. Journal of Applied Physics, 2007, 101(3): 033713-1–033713-7CrossRefGoogle Scholar
  12. 12.
    Exarhos G J, Zhou X D. Discovery-based design of transparent conducting oxide films. Thin Solid Films, 2007, 515(18): 7025–7052CrossRefGoogle Scholar
  13. 13.
    Faÿ S. Science of Microtechnique, Institute of Procuction and Robotic, écolePolytechniqueFédérale de Lausanne, Lausanne, 2003Google Scholar
  14. 14.
    Kumar V, Singh R G, Purohit L P, Mehra R M. Structural, transport and optical properties of boron-doped zinc oxide nanocrystalline. Journal of Materials Science and Technology, 2011, 27(6): 481–488CrossRefGoogle Scholar
  15. 15.
    Huang Q, Wang Y, Wang S, Zhang D, Zhao Y, Zhang X. Transparent conductive ZnO:B films deposited by magnetron sputtering. Thin Solid Films, 2012, 520(18): 5960–5964CrossRefGoogle Scholar
  16. 16.
    Ton-That C, Foley M, Phillips MR, Tsuzuki T, Smith Z. Correlation between the structural and optical properties of Mn-doped ZnO nanoparticles. Journal of Alloys and Compounds, 2012, 522: 114–117CrossRefGoogle Scholar

Copyright information

© Higher Education Press and Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Dong Xu
    • 1
  • Sheng Yin
    • 1
  • Xiangbin Zeng
    • 1
  • Song Yang
    • 1
  • Xixing Wen
    • 1
  1. 1.School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhanChina

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