Interfacial Layer Effect on Novel p-Ni1-xO:Li/n-Si Heterojunction Solar Cells

Authors: Feng-Hao Hsu, Na-Fu Wang, Yu-Zen Tsai, Yu-Song Cheng, Cheng-Fu Yang, Mau-Phon Houng

Abstract:

This study fabricates p-type Ni_1−xO:Li/n-Si heterojunction solar cells (P⁺/n HJSCs) by using radio frequency (RF) magnetron sputtering and investigates the effect of substrate temperature on photovoltaic cell properties. Grazing incidence x-ray diffraction, four point probe, and ultraviolet-visible-near infrared discover the optoelectrical properties of p-Ni_1-xO thin films. The results show that p-Ni_1-xO thin films deposited at 300 ^oC has the highest grain size (22.4 nm), average visible transmittance (~42%), and electrical resistivity (2.7 Ωcm). However, the conversion efficiency of cell is shown only 2.33% which is lower than the cell (3.39%) fabricated at room temperature. This result can be mainly attributed to interfacial layer thickness (SiO_x) reduces from 2.35 nm to 1.70 nm, as verified by high-resolution transmission electron microscopy.

Keywords: Heterojunction, nickel oxide, solar cells, sputtering.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1094006

References:

[1] N.L. Panwar, S.C. Kaushik, S. Kothari, "Role of renewable energy sources in environmental protection: A review,” Renew. Sust. Energ. Rev., vol. 15, pp. 1513-1524, Apr. 2011.
[2] D.M. Chapin, C.S. Fuller and G.L. Pearson, "A New Silicon p-n Junction Photocell for Converting Solar Radiation into Electrical Power,” J. Appl. Phys., vol. 25, pp. 676-677, May 1954.
[3] J. Zhao, A. Wang, M.A. Green, F. Ferrazza, "19.8% efficient "honeycomb” textured multicrystalline and 24.4% monocrystalline silicon solar cells,” Appl. Phys. Lett., vol. 73, pp. 1991-1993, Oct. 1998.
[4] M. Taguchi, K. Kawamoto, S. Tsuge, T. Baba, H. Sakata, M. Morizane, K. Uchihashi, N. Nakamura, S. Kiyama, O. Oota, "HITTM cells-high-efficiency crystalline Si cells with novel structure,” Prog. Photovolt: Res., Appl. vol.73, pp. 503-513, Oct. 2000.
[5] H.W. Fang, T.E. Hsieh, J.Y. Juang, "Effects of indium concentration on the efficiency of amorphous In-Zn-O/SiOx/n-Si hetero-junction solar cells,” Sol. Energy Mater. Sol. Cells, vol. 121, pp. 176-181, Feb. 2014.
[6] H.W. Fang, S.J. Liu, T.E. Hsieh, J.Y. Juang, J.H. Hsieh, "Fabrication and characterization of amorphous In-Zn-O/SiOx/n-Si heterojunction solar cells,” Sol. Energy, vol. 85, pp. 2589-2594, Nov. 2011.
[7] D. Song, A.G. Aberle, and J. Xia, "Optimisation of ZnO:Al films by change of sputter gas pressure for solar cell application,” Appl. Surf. Sci., vol. 195, pp. 291-296, Jul. 2007.
[8] F.H. Hsu, N.F. Wang, Y.Z. Tsai, M.P. Houng, "A novel Al and Y codoped ZnO/n-Si heterojunction solar cells fabricated by pulsed laser deposition,” Sol. Energy, vol. 86, pp. 3146-2594, Nov. 2012.
[9] J. Kim, J.H. Yun, Y.C. Park, W.A. Anderson, "Transparent and crystalline Al-doped ZnO film-embedded heterojunction Si solar cell,” Mater. Lett. vol. 75, pp. 99-101, May 2012.
[10] N.F. Wang, Y.Z. Tsai, F.H. Hsu, "Effect of Surface Texture on Al-Y Codoped ZnO/n-Si Heterojunction Solar Cells,” IEEE Trans. Electron Devices, vol. 60, pp. 4073-4078, Dec. 2013.
[11] F.H. Hsu, N.F. Wang, Y.Z. Tsai, M.C. Chuang, Y.S. Cheng, M.P. Houng, "Study of working pressure on the optoelectrical properties of Al–Y codoped ZnO thin-film deposited using DC magnetron sputtering for solar cell applications,” Appl. Surf. Sci., vol. 280, pp. 104-108, Sep. 2013.
[12] H. Kobayashi, Y.L. Liu, Y. Yamashita, J. Ivanco, S. Imai, M. Takahashi, "Methods of observation and elimination of semiconductor defect states,” Sol. Energy, vol. 80, pp. 645-652, Jun. 2006.
[13] F.H. Hsu, N.F. Wang, Y.Z. Tsai, Y.S. Song, M.P. Houng, "A new p-Ni1−xO:Li/n-Si heterojunction solar cell fabricated by RF magnetron sputtering,” J. Phys. D:Appl. Phys., vol. 46, pp. 275104(8), Jul. 2013.
[14] Y.M. Lu, W.S. Hwang, J.S. Yang, "Effects of substrate temperature on the resistivity of non-stoichiometric sputtered NiOx films,” Surf. Coat. Technol. vol. 155, pp. 231-235, Jun. 2002.
[15] Y.Z. Tsai, N.F. Wang, M.R. Tseng, and F.H. Hsu, "Transparent conducting Al and Y codoped ZnO thin film deposited by DC sputtering,” Mater. Chem. Phys., vol. 123, pp. 300-303, Sep. 2010.
[16] J.F. Chang, M.H. Hon, "The effect of deposition temperature on the properties of Al-doped zinc oxide thin films,” Thin Solid Films, vol. 386, pp. 79-86, May 2001.
[17] W.L. Jang, Y.M. Lu, W.S. Hwang, T.L. Hsiung, "Point defects in sputtered NiO films,” Appl. Phys. Lett., vol. 94, pp. 062103-062103-3, Feb. 2009.
[18] Y. Zhou, D. Gu, Y. Geng, F. Gan, "Thermal, structural and optical properties of NiOx thin films deposited by reactive dc-magnetron sputtering,” Mater. Sci. Eng. B, vol. 135, pp. 125-128, Nov. 2006.
[19] W.W. Wenas, S. Riyadi, "Carrier transport in high-efficiency ZnO/SiO2/Si solar cells,” Sol. Energy Mater. Sol. Cells, vol. 90, pp. 3261-3267, Nov. 2006.
[20] H.W. Fang, T.E. Hsieh, J.Y. Juang, "Influences of SiOx layer thickness on the characteristics of In-Zn-O/SiOx/n-Si hetero-junction structure solar cells,” Surf. Coat. Technol., vol. 231, pp. 214-218, Sep. 2013.