Laser Recovery of Subsurface Damages in Chemomechanically Polished Silicon Wafers

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Silicon wafers are the most widely used semiconductor substrates. It has been considered that silicon wafers after chemomechanical polishing (CMP) have no subsurface defects. However, in fact, defects such as dislocation and latent microcracks will remain in the wafers if CMP is performed under unsuitable conditions. In this study, we confirmed the existence of subsurface damages at a depth of submicron level in a silicon wafer after CMP, then used a nanosecond pulsed Nd:YAG laser to repair the subsurface damages. It was found that subsurface defects were recovered to a single crystalline structure by laser irradiation without changing the surface topography. The phase transformation of silicon before and after laser irradiation was confirmed by laser Raman spectroscopy and chemical etching using saturated aqueous solution of Ca(OH)2. The findings from this study contributes to improve the quality of silicon wafers for high-performance semiconductors.

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97-100

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July 2016

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© 2016 Trans Tech Publications Ltd. All Rights Reserved

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[1] Z.J. Pei, G.R. Fisher, J. Liu, Grinding of silicon wafers: A review from historical perspectives, Int. J. Machine Tools & Manufacture, 48 (2008) 1297-1307.

DOI: 10.1016/j.ijmachtools.2008.05.009

Google Scholar

[2] J. Xu, J.B. Luo, L.L. Wang, X.C. Lu, The crystallographic change in sub-surface layer of the silicon single crystal polished by chemical mechanical polishing, Tribo. Int. 40 (2007) 285-289.

DOI: 10.1016/j.triboint.2005.09.034

Google Scholar

[3] Y. Ogita, K. Kobayashi, H. Daio, Photoconductivity characterization of silicon wafer mirror-polishing subsurface damage related to gate oxide integrity, J. Cryst. Growth, 210 (2000) 36-39.

DOI: 10.1016/s0022-0248(99)00642-9

Google Scholar

[4] J. Yan, T. Asami, T. Kuriyagawa, Response of machining-damaged single-crystalline silicon wafers to nanosecond pulsed laser irradiation, Semicond. Sci. Technol. 22 (2007) 392-395.

DOI: 10.1088/0268-1242/22/4/016

Google Scholar

[5] J. Yan, S. Sakai, H. Isogai, K. Izunome, Recovery of microstructure and surface topography of grinding-damaged silicon wafers by nanosecond-pulsed laser irradiation, Semicond. Sci. Technol. 24 (2009) 105018-105023.

DOI: 10.1088/0268-1242/24/10/105018

Google Scholar

[6] J. Yan, F. Kobayashi, Laser recovery of machining damage under curved silicon surface, CIRP Ann. – Manuf. Tech., 62 (2013) 199-202.

DOI: 10.1016/j.cirp.2013.03.109

Google Scholar

[7] J. Frühauf, Shape and Functional Elements of the Bulk Silicon Microtechnique – A Manual of Wet-Etched Silicon Structures, Springer Berlin Heidelberg, New York, 2005, p.7.

Google Scholar

[8] S. Steffens, C. Becker, J. -H. Zollondz, A. Chhowdhury, A. Slaoui, S. Lindekugel, Defect annealing processes for polycrystalline silicon thin-film solar cells, Mat. Sci. Eng. B, 178 (2013) 670-675.

DOI: 10.1016/j.mseb.2012.11.002

Google Scholar