Ray Tracing of Light Trapping Schemes in Thin Crystalline Silicon for Photovoltaics

Abstract:

Thin crystalline silicon (c-Si) suffers from poor light absorption which hinders generation of high photocurrent in photovoltaic (PV) devices. To overcome this issue, efficient light trapping (LT) schemes need to be incorporated into the thin c-Si absorber. This paper presents ray tracing of LT schemes in thin c-Si to enhance broadband light absorption within 300-1200 nm wavelength region. For the ray tracing, mono c-Si wafer with 100 μm thickness is investigated and solar spectrum (AM1.5G) at normal incidence is used. Front and rear pyramid textures, silicon nitride (SiN_x) anti-reflective coating (ARC) and back surface reflector (BSR) are the LT schemes being studied in this work. With incremental LT schemes, optical properties of the thin c-Si are analyzed. From the absorption curve, maximum potential photocurrent density (J_max) is calculated, assuming unity carrier collection. The c-Si reference (without LT) exhibits J_max of 24.93 mA/cm². With incorporation of incremental LT schemes into the thin c-Si, the J_max increases, owing to enhanced light coupling and light scattering in the c-Si absorber. The J_max up to 42.12 mA/cm² is achieved when all the LT schemes are incorporated into the thin c-Si absorber. This represents 69% enhancement when compared to the J_max of the c-Si reference.

• Periodical: Solid State Phenomena (Volume 301)
• Pages: 183-191
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.301.183
• Online since: March 2020
• Authors: Mohd Zamir Pakhuruddin*
• Keywords: Absorption, Light Trapping, Photovoltaics, Ray Tracing, Silicon

References

[1] M. A. Green, Commercial progress and challenges for photovoltaics, Nature Energy 1 (2016) 15015-1 – 15015-5.

[2] L. Andreani, A. Bozzola, P. Kowalczewski, M. Liscidini, L. Redorici, Silicon solar cells: toward the efficiency limits, Advances in Physics: X 4 (2018) 1548305-1 - 1548305-24.

DOI: 10.1080/23746149.2018.1548305

[3] Information on https://itrpv.vdma.org/.

[4] P. P. Altermatt, Y. Chen, Y. Yang, A. Ali, P. J. Verlinden, Optical properties of industrially mass-produced crystalline silicon solar cells and prospects for improvements, in Light, Energy and the Environment, OSA Technical Digest (online) (Optical Society of America, 2016), Paper JTh1A.2.

DOI: 10.1364/fts.2016.jth1a.2

[5] D. Payne, T.H. Fung, M.U. Khan, J.C. Campa, K. McIntosh, M. Abbott, Understanding the optics of industrial black silicon, AIP Conference Proceedings 1999 (2018) 050007-1-050007-8.

DOI: 10.1063/1.5049297

[6] Y. Wan, K. McIntosh, A. F. Thomson, Characterisation and optimisation of PECVD SiNx as an antireflection coating and passivation layer for silicon solar cells, AIP Advances 3 (2013) 032113-1 – 032113-14.

DOI: 10.1063/1.4795108

[7] C. Barugkin, F. J. Beck, K. R. Catchpole, Diffuse reflectors for improving light management in solar cells: A review and outlook, Journal of Optics 19 (2017) 014001-1 - 014001-2.

DOI: 10.1088/2040-8978/19/1/014001

[8] K. McIntosh, M. Abbott, B. Sudbury, Ray tracing isotextured solar cells, Energy Procedia 92 (2016) 122-129.

DOI: 10.1016/j.egypro.2016.07.041

[9] Information on https://www.pvlighthouse.com.au/.

[10] O. Höhn, N. Tucher, B. Bläsi, Impact of front side pyramid size on the light trapping performance of wafer-based silicon solar cells and modules, IEEE 44th Photovoltaic Specialist Conference (PVSC) (2017).

DOI: 10.1109/pvsc.2017.8366607

[11] S. C. Baker-Finch, K. R. McIntosh, Reflection of normally incident light from silicon solar cells with pyramidal texture, Progress in Photovoltaics: Research and Applications 19 (2011) 406-416.

DOI: 10.1002/pip.1050

[12] K. W. A. Chee, Z. Tang, H. Lü, F. Huang, Anti-reflective structures for photovoltaics: Numerical and experimental design, Energy Reports 4 (2018) 266-273.

DOI: 10.1016/j.egyr.2018.02.002

[13] Information on https://rredc.nrel.gov/solar//spectra/am1.5/.

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

DOI: 10.1016/j.solener.2017.04.069

[15] M. Z. Pakhuruddin, J. Huang, J. Dore, S. Varlamov, Rear texturing for light-trapping in laser-crystallised silicon thin-film solar cells on glass, Solar Energy 166 (2018) 213-219.

DOI: 10.1016/j.solener.2018.03.055

[16] M. Z. Pakhuruddin, J. Huang, J. Dore, S. Varlamov, Enhanced absorption in laser-crystallized silicon thin films on textured glass, IEEE Journal of Photovoltaics 6 (2016) 852-859.

DOI: 10.1109/jphotov.2016.2545410

[17] A. Najar, J. Charrier, P. Pirasteh, R. Sougrat, Ultra-low reflection porous silicon nanowires for solar cell applications, Optics Express 20 (2012) 16861-1 - 16861-10.

DOI: 10.1364/oe.20.016861

[18] J. K. Selj, D. Young, S. Grover, Optimization of the antireflection coating of thin epitaxial crystalline silicon solar cells, Energy Procedia 77 (2015) 248-252.

DOI: 10.1016/j.egypro.2015.07.035

[19] M. A. Green, The path to 25% silicon solar cell efficiency: History of silicon cell evolution, Progress in Photovoltaics: Research and Applications 17 (2009) 183-189.

DOI: 10.1002/pip.892

[20] F. Haase, S. Eidelloth, R. Horbelt, K. Bothe, E. G. Rojas, R. Brendel, Loss analysis of back-contact back-junction thin-film monocrystalline silicon solar cells, Journal of Applied Physics 110 (2011) 124510-1 – 124510-9.

DOI: 10.1063/1.3669388

[21] T. Tiedje, E. Yablonovitch, G. D. Cody, B. G. Brooks, Limiting efficiency of silicon solar cells, IEEE Transactions on Electron Devices, 31 (1984) 711-716.

DOI: 10.1109/t-ed.1984.21594