Potential Routes for Recycling and Reuse of Silicon Kerf


Article Preview

In photovoltaic industry during wafer sawing significant amount of solar grade silicon is getting lost into sawing slurry. In the present paper, potential approach and routes for recycling and reuse of silicon wafer sawing slurry are explored. Various techniques were used including distillation, heavy liquid separation, acid leaching and high temperature processing. After distillation, the polyethylene glycol (PEG) can be separated and reused as lubricant. By dissolving silicon at high temperatures from the kerf into a clean molten pool of silicon metal or scrap, or into an alloying metal like Cu, SiC can also be separated and recovered. Depending on the impurity level, solar grade silicon can be finally produced from this waste stream in combination with necessary refining treatment for the applications in the PV industry. Furthermore, converting the kerf into SiC or Si3N4 particles as technical ceramic products is also explored. It is expected that the present research can pave a way to develop a total recycling route for an optimum use of this resource, and to minimize the environmental risk of the waste disposal.



Advanced Materials Research (Volumes 295-297)

Edited by:

Pengcheng Wang, Liqun Ai, Yungang Li, Xiaoming Sang and Jinglong Bu




Y. P. Xiao and Y. X. Yang, "Potential Routes for Recycling and Reuse of Silicon Kerf", Advanced Materials Research, Vols. 295-297, pp. 2235-2240, 2011

Online since:

July 2011




[1] Ceccaroli, B. and Friestad, K., Refining of Metallurgical Grade Silicon, US patent No. 6, 861, 040, (2005).

[2] Müller, A. and Nasch, P. RE-Si-CLE: Recycling of Silicon Rejects from PV Production Cycle. Active Solar Energy Photovoltaic Programme Summary Report 2004; Swiss Federal Office of Energy SOFE.

[3] Smithells Metals Reference Book, 8th edition, Eds. W.F. Gale & T.C. Totmeie. Elsevier, Amsterdam, (2004).

[4] Chang, Y., Apparatus for Recycling the Disposed Slurry Produced in the Manufacturing Process of the Silicon Wafer. WO 2008/013327 A1.

[5] Alsema, E. A. and de Wild-Scholten, M.J., Keeping It Clean: Reducing Environmental Impacts from Solar PV, Renewable Energy World, Vol. 10, Issue 6, November / December (2007).

[6] Billiet, R. L. and Nguyen, H.T., Photovoltaic cells from silicon kerf, US patent No. 6780665 B2, Aug. 24, (2004).

[7] Wang, T.Y., Lin, Y.C., Tai, C.Y., Sivakumar, R., Rai, D.K. and Lan, C.W. A novel approach for recycling of kerf loss silicon from cutting slurry waste for solar cell application. Journal of Crystal Growth, 310, 3403-3406 (2008).

DOI: https://doi.org/10.1016/j.jcrysgro.2008.04.031

[8] Wang, T.Y., Lin, Y.C., Tai, C.Y., Fei, C.C., Tseng, M.Y. and Lan, C.W. Recovery of silicon from kerf loss slurry waste for photovoltaic applications. Prog. Photovolt: Res. Appl. 17, 155-163 (2009).

DOI: https://doi.org/10.1002/pip.863

[9] Ciftja, A., Zhang, L., and Engh, T.A., Removal of SiC and Si3N4 Particles from Silicon Scrap By Foam Filters. Recycling and Waste Processing, eds. M. Schlesinger et al., TMS, 67-76 (2007).

[10] Kongstein, O.E., Wollan, C., Sultana, S. and Haarberg, G.M., Electrorefining of Silicon in molten calcium chloride, ECS Transactions, 3, 357-361, (2007).

DOI: https://doi.org/10.1149/1.2798679

[11] Mühlbauer, A., Diers, V. and Walther, A., Removal of C/SiC from liquid silicon by directional solidification. Journal of Crystal Growth, 108, 41-52, (1991).

DOI: https://doi.org/10.1016/0022-0248(91)90352-6

Fetching data from Crossref.
This may take some time to load.