Etching, Evaporated Contacts and Antireflection Coating on Multicrystalline Silicon Solar Cell

Abstract

This work has focuses on the development of a simple and low cost alternative to these deposited coatings (ARC) , through the use of an electrochemical etching technique to form AR layers of silicon (mc-Si). This is considered as the proper etching process for mc-Si. Also, silicon oxide (SiO) and titanium oxide (TiO2) coatings have been used to reduce the reflection losses from silicon solar cells. More than 20.6% enhancement in the short circuit current has been demonstrated in the polished cells using evaporated SiO antireflection coating. Additionally more than 12% enhancement in the short circuit current has been observed after TiO2 antireflection coating. The output current is found almost directly proportional to light intensity.

Keywords

• ARC; electrochemical etching technique; multicrystalline Silicon Solar cell; reflection losses; polished cells.

References

1. M. A. Green, Silicon Solar Cells: Advanced Principles and Practice, Centre for Photovoltaic Devices and Systems, Sydney, 1995.
2. Zhao, J. Wang, A. Campbell, P. Green, M.A., 22.7% efficient silicon photovoltaic modules with textured front surface , Electron Devices, IEEE Transactions on, Volume: 46 Issue: 7, pp:1495 - 1497, 1999. ISSN: 0018
3. M. j. Mecann, K. e. Catchpole, K. J. Weber, A. W. Blakers, Sol. Ener. Mater. Sol. Cells 68, 135, 2001.
4. S. Reber, W. Zimmemnan, T. Kielba,, Sol. Ener. Mater. Sol. Cells 65, 409, 2001.
5. C. j. Brabec, N. S. Sariciftci, and J. C. Hummelen, "Plastic Solar Cells", Adv. Funct. Mater11, No. 1, pp 15- , 2001.
6. A. Combert, "Future Steps Towards Large-Area Microstructures Surfaces", in M. Weck (Ed.), "Precision Engineering and Micro Technology", 195-203, 2000.
7. Ph. Lalanne, G. M. Morries, "Highly imporoved coupled-wave polarization", J. Opt. Soc. Am. A 13, 779-784, 1996. method for TM
8. H. J. Möller, Solid State Phenomena, Vols, 47-48, pp. 142, 1996.

9. Sexton, F. W. , Plasma nitrade AR coating for silicon solar cells. Solar Energy Mat., 7,1- 4, 1991.
10. Kishore, R. , Singh, S. N. and Das, B. K., PECVD grown silicon nitrade AR coating on polycrstalline silicon solar cells. Solar Energy Mat. Solar cells, 26, 27-35, Kishore, R., Singh, S. N. and Das, B.K. Growth of silicon nitrade films on single and multicrystalline silicon solar cell using PECVD Technique. 6th int. Photovoltaic Sc. Engng. Conf., New Delhi, India, pp 249-253, 1992
11. Ramkishore, S.N. Singh and B.K.Das, Screen printer Titanium oxide and pecvd silicon nitrade as antireflection coating on silicon solar cells, Renewable Energy, Vol. 12, pp. 131-135, 1997.
12. Chen, Z., Sana, P., Rohatgi, A., A novel and effective PECVD SiO2/SiN antireflection coating for Si Solar cells. IEEE Trans. Electron Devices, 40, 1161- , 1993.
13. Narayanan, S., Ronein, S. and Wohlgemuth, J., Silicon nitade AR coating for low cost silicon solar cells. th Int. Photovoltaic Sc. Eneng. Conf., New Delhi, India 136, 1992.
14. H. J. Hovel.‘TiO2 antireflection coating by a low temperature spray process,‘ J. Electrochem. Soc., Soild- State Sci. Technol. Vol. 125, No.6, pp. 983-985, 1978.
15. A. Moussi and G. Sala, .‘TiO2 antireflection layer sprayed on textured surface,‘ in Proc. 18 th E. C. Photovoltaic Sol Energy Conf. 198, Vol2, pp.1374-7.
16. S. Strehlke, S. Bastide, J. Guillet, C.Levy-Clement, Material Science and Engineering B69-70, PP. 81-86, O. S. Heavens, Optical properties of thin films, Dover, New York, 1965.
17. A. M. Goodman. Appl. Optics 17 (1978) 2779.
18. H. Nouri, M. Bouaïcha, B. Bessaïs , " Effect of porous silicon on the performances of silicon solar cells during the porous silicon-based gettering procedure" Solar Energy Materials and Solar Cells, Volume 93, Issue , October 2009, Pages 1823-1826
19. Alexei Deinega, Ilya Valuev, Boris Potapkin, and Yurii Lozovik, Antireflective properties of pyramidally textured surfaces, Optics Letters, Vol. 35, Issue 2, pp. 108 (2010) http://dx.doi.org/10.1364/OL.35.000106
20. B. L. Sopori, R. A. Pryor. Solar Cells 8 (1983) 249 Appendix
21. Table 1. Preparation condition of the cold metallization procedure Metal Al (200nm) Etch away None Kern (NH4OH:H2O2+HCL: H2O2) Boiling H2SO4 + (NH4)2S2O8 Boiling HNO3 Al (200nm) Lift off M17 Al (200nm) Cr(2nm)/Cu(2 nm) (NH4)2S2O8 M20