Broadband Anti-Reflection in Black Silicon Fabricated by Two-Step Silver-Assisted Wet Chemical Etching for Photovoltaics

Abstract:

This paper reports broadband anti-reflection in black silicon (b-Si) fabricated by two-step metal-assisted chemical etching (MACE) for potential photovoltaic (PV) applications. The method involves deposition of silver nanoparticles (Ag NPs) in aqueous solution of HF:AgNO₃, followed by etching in HF:H₂O₂:DI H₂O solution for different duration (10-25 s). Effects of etching time towards surface morphological and optical properties of b-Si nanowires are investigated. Surface morphological characterization confirms presence of b-Si nanowires with heights of 350-570 nm and diameter of 150-300 nm. The b-Si nanowires exhibit outstanding broadband anti-reflection due to refractive index grading effect. This is represented as weighted average reflection (WAR) in the 300-1100 nm wavelength region. After 20 s of etching, b-Si nanowires with height of 570 nm and width of about 200 nm are produced. The nanowires demonstrate WAR of 5.5%, which represents the lowest WAR in this investigation. This results in absorption of 95.6% at wavelength of 600 nm. The enhanced broadband light absorption yields maximum potential short-circuit current density (J_sc(max)) of up to 39.7 mA/cm², or 51% enhancement compared to c-Si reference. This facile b-Si fabrication method for broadband enhanced anti-reflection could be a promising technique to produce potential PV devices with high photocurrent.

• Periodical: Solid State Phenomena (Volume 301)
• Pages: 167-174
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.301.167
• Online since: March 2020
• Authors: Auwal Abdulkadir, Nur Afidah Md. Noor, Azlan Abdul Aziz, Mohd Zamir Pakhuruddin*
• Keywords: Anti-Reflection, Black Silicon, Nanowires, Refractive Index Grading, Silver-Assisted Etching

References

[1] C. Battaglia, A. Cuevas, and S. De Wolf, High-efficiency crystalline silicon solar cells: Status and perspectives,, Energy Environ. Sci., vol. 9, no. 5, p.1552–1576, (2016).

DOI: 10.1039/c5ee03380b

[2] Y. F. Zhuang, S. H. Zhong, Z. G. Huang, and W. Z. Shen, Versatile strategies for improving the performance of diamond wire sawn mc-Si solar cells,, Sol. Energy Mater. Sol. Cells, vol. 153, p.18–24, (2016).

DOI: 10.1016/j.solmat.2016.04.014

[3] E. Vazsonyi, K. De Clercq, R. Einhaus, E. Van Kerschaver, K. Said, J. Poortmans, J. Szlufcik, and J. Nijs, Improved anisotropic etching process for industrial texturing of silicon solar cells,, Sol. Energy Mater. Sol. Cells, vol. 57, no. 2, p.179–188, (1999).

DOI: 10.1016/s0927-0248(98)00180-9

[4] Y. Wang, L. Yang, Y. Liu, Z. Mei, W. Chen, J. Li, H. Liang, A. Kuznetsov, and D. Xiaolong, Maskless inverted pyramid texturization of silicon,, Sci. Rep., vol. 5, no. 0316, p.1–7, (2015).

DOI: 10.1038/srep10843

[5] Z. Zhao, P. Li, Y. Wei, C. Lu, X. Tan, and A. Liu, 17.3% Efficient Black Silicon Solar Cell Without Dielectric Antireflection Coating,, Sol. Energy, vol. 110, p.714–719, (2014).

DOI: 10.1016/j.solener.2014.10.029

[6] M. Otto, M. Algasinger, H. Branz, B. Gesemann, T. Gimpel, K. Füchsel, T. Käsebier, S. Kontermann, S. Koynov, X. Li, V. Naumann, J. Oh, A. N. Sprafke, J. Ziegler, M. Zilk, and R. B. Wehrspohn, Black silicon photovoltaics,, Adv. Opt. Mater., vol. 3, no. 2, p.147–164, (2015).

DOI: 10.1364/pv.2014.ptu2c.2

[7] W. K. To, C. H. Tsang, H. H. Li, and Z. Huang, Fabrication of n-type mesoporous silicon nanowires by one-step etching,, Nano Lett., vol. 11, no. 12, p.5252–5258, (2011).

DOI: 10.1021/nl202674t

[8] F. Es, M. Kulakci, and R. Turan, An Alternative Metal-Assisted Etching Route for Texturing Silicon Wafers for Solar Cell Applications,, IEEE J. Photovoltaics, vol. 6, no. 2, p.440–446, (2016).

DOI: 10.1109/jphotov.2016.2520207

[9] Z. Huang, N. Geyer, P. Werner, J. De Boor, and U. Gösele, Metal-assisted chemical etching of silicon: A review,, Adv. Mater., vol. 23, no. 2, p.285–308, (2011).

DOI: 10.1002/adma.201001784

[10] J. Oh, H. C. Yuan, and H. M. Branz, An 18.2%-efficient black-silicon solar cell achieved through control of carrier recombination in nanostructures,, Nat. Nanotechnol., vol. 7, no. 11, p.743–748, (2012).

DOI: 10.1038/nnano.2012.166

[11] M. Z. Pakhuruddin, J. Huang, J. Dore, and S. Varlamov, Enhanced light-trapping in laser-crystallised silicon thin-film solar cells on glass by optimised back surface reflectors,, Sol. Energy, vol. 150, p.477–484, (2017).

DOI: 10.1016/j.solener.2017.04.069

[12] N. A. M. Noor, S. K. Mohamad, S. S. Hamil, M. Devarajan, and M. Z. Pakhuruddin, Effects of etching time towards broadband absorption enhancement in black silicon fabricated by silver-assisted chemical etching,, Optik (Stuttg)., vol. 176, no. November 2018, p.586–592, (2019).

DOI: 10.1016/j.ijleo.2018.09.096

[13] S. K. Srivastava, D. Kumar, Vandana, M. Sharma, R. Kumar, and P. K. Singh, Silver catalyzed nano-texturing of silicon surfaces for solar cell applications,, Sol. Energy Mater. Sol. Cells, vol. 100, p.33–38, (2012).

DOI: 10.1016/j.solmat.2011.05.003

[14] C. Chartier, S. Bastide, and C. Lévy-Clément, Metal-assisted chemical etching of silicon in HF-H2O2,, Electrochim. Acta, vol. 53, no. 17, p.5509–5516, (2008).

DOI: 10.1016/j.electacta.2008.03.009

[15] W. Kern, The Evolution of Silicon Wafer Cleaning Technology,, J. Electrochem. Soc., vol. 137, no. 6, p.1887, (1990).

[16] N. A. M. Noor, S. K. Mohamad, S. S. Hamil and M. Z. Pakhuruddin, Effects of annealing temperature towards surface morphological and optical properties of black silicon fabricated by silver-assisted chemical etching,, Mater. Sci. Semicond. Process., vol. 91, p.167–173, (2019).

DOI: 10.1016/j.mssp.2018.11.006

[17] M. Z. Pakhuruddin, J. Huang, J. Dore, and S. Varlamov, Enhanced Absorption in Laser-Crystallized Silicon Thin Films on Textured Glass,, IEEE J. Photovoltaics, vol. 6, no. 4, p.852–859, (2016).

DOI: 10.1109/jphotov.2016.2545410

[18] M. Abouda Lachiheb, N. Nafie, and M. Bouaicha, The dual role of silver during silicon etching in HF solution,, Nanoscale Res. Lett., vol. 7, p.3–7, (2012).

DOI: 10.1186/1556-276x-7-455

[19] K. Peng, A. Lu, R. Zhang, and S. T. Lee, Motility of metal nanoparticles in silicon and induced anisotropic silicon etching,, Adv. Funct. Mater., vol. 18, no. 19, p.3026–3035, (2008).

DOI: 10.1002/adfm.200800371

[20] Z. R. Smith, R. L. Smith, and S. D. Collins, Electrochimica Acta Mechanism of nanowire formation in metal assisted chemical etching,, vol. 92, p.139–147, (2013).

DOI: 10.1016/j.electacta.2012.12.075

[21] C. H. Hsu, J. R. Wu, Y. T. Lu, D. J. Flood, A. R. Barron, and L. C. Chen, Fabrication and characteristics of black silicon for solar cell applications: An overview,, Mater. Sci. Semicond. Process., vol. 25, p.2–17, (2014).

DOI: 10.1016/j.mssp.2014.02.005

[22] X. He, S. Li, W. Ma, Z. Ding, J. Yu, B. Qin, J. Yang, Y. X. Zou, and J. Qiu, A simple and low-cost chemical etching method for controllable fabrication of large-scale kinked silicon nanowires,, Mater. Lett., vol. 196, p.269–272, (2017).

DOI: 10.1016/j.matlet.2017.03.131

[23] S. Li, W. Ma, X. Chen, K. Xie, Y. Li, X. He, X. Yang, and Y. Lei, Structure and antireflection properties of SiNWs arrays form mc-Si wafer through Ag-catalyzed chemical etching,, Appl. Surf. Sci., vol. 369, p.232–240, (2016).

DOI: 10.1016/j.apsusc.2016.02.028