0
Research Papers

Fracture Analysis and Distribution of Surface Cracks in Multicrystalline Silicon Wafers

[+] Author and Article Information
S. Saffar

Department of Structural Engineering,
Norwegian University of Science and Technology,
Trondheim NO-7491, Norway

S. Gouttebroze

SINTEF Materials and Chemistry,
Oslo NO-0314, Norway

Z. L. Zhang

Department of Structural Engineering,
Norwegian University of Science and Technology,
Trondheim NO-7491, Norway
e-mail: zhiliang.zhang@ntnu.no

Usually, for the ith strength value Pf,i = (i − 0.5)/N, where N is the total number of measurements.

1Corresponding author.

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING. Manuscript received July 2, 2013; final manuscript received October 31, 2013; published online December 19, 2013. Assoc. Editor: Santiago Silvestre.

J. Sol. Energy Eng 136(2), 021024 (Dec 19, 2013) (9 pages) Paper No: SOL-13-1189; doi: 10.1115/1.4025972 History: Received July 02, 2013; Revised October 31, 2013

Solar silicon wafers are mainly produced through multiwire sawing. The sawing process induces micro cracks on the wafer surface, which are responsible for brittle fracture. Hence, it is important to scrutinize the crack geometries most commonly generated in silicon wafer sawing or handling process and link the surface crack to the fracture of wafers. The fracture of a large number of multicrystalline silicon wafers has been investigated by means of 4-point bending and twisting tests and a failure probability function is presented. By neglecting the material property variation and assuming that one surface crack is dominating the wafer breakage, 3D finite element models with various crack sizes (depth, length, and orientation) have been analyzed to identify the distribution of surface crack geometries by fitting the failure probability from the experiments. With respect to the 63% probability, the existing surface cracks in the wafers studied appear to have depth and length ratios less than 0.042 and 0.19, respectively. Furthermore, it has been shown that the surface cracks with depth in the range from 10 to 20 μm, length up to 10 mm and angles in the range of 30 deg–60 deg, can be considered as the most common crack geometries in wafers we tested. Finally, it has been found that the mechanical strength of the wafers tested parallel to the sawing direction is approximately 15 MPa smaller than those tested perpendicular to the sawing direction.

FIGURES IN THIS ARTICLE
<>
Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Zhang, L. C., Biddut, A. Q., and Ali, Y. M., 2010, “Dependence of Pad Performance on Its Texture in Polishing Mono-Crystalline Silicon Wafers,” Int. J. Mech. Sci., 52, pp. 657–663. [CrossRef]
Zarudi, I., and Han, B. S., 2003, “Deformation and Material Removal Rate in Polishing Silicon Wafers,” J. Mater. Process. Technol., 140, pp. 641–645. [CrossRef]
Li, Z. C., Pei, Z. J., and Fisher, G. R., 2006, “Simultaneous Double Side Grinding of Silicon Wafers: A Literature Review,” Int. J. Mach. Tools Manuf., 46, pp. 1449–1458. [CrossRef]
Pei, Z. J., Xin, X. J., and Liu, W., 2003, “Finite Element Analysis for Grinding of Wire-Sawn Silicon Wafers,” Int. J. Mach. Tools Manuf., 43, pp. 7–16. [CrossRef]
Qian, J., Steegen, S., Vander Poorten, E. B., Reynaerts, D., and van Brussel, H., 2002, “EDM Texturing of Multicrystalline Silicon Wafer and EFG Ribbon for Solar Cell Application”, Int. J. Mach. Tools Manuf., 42, pp. 1657–1664. [CrossRef]
Stefancich, M., Butturi, M., Vincenzi, D., and Martinelli, G., 2001, “Mechanical Effects of Chemical Etchings on Monocrystalline Silicon for Photovoltaic Use,” Sol. Energy Mater. Sol. Cells, 69, pp. 371–377. [CrossRef]
Ranjan, M., Gopalakrishnan, L., Srihari, K., and Woychik, C., 1998, “Die Cracking in Flip Chip Assemblies,” 48th IEEE Electronic Components and Technology Conference, Seattle, WA, May 25-28, pp. 729–733. [CrossRef]
Shkarayev, S., Savastiouk, S., and Siniaguine, O., 2003, “Stress and Reliability Analysis of Electronic Packages With Ultra-Thin Chips,” ASME J. Electron. Packag., 125, pp. 98–103. [CrossRef]
Mercado, L. L., Wieser, H., and Hauck, T., 2003, “Multichip Package Delamination and Die Fracture Analysis,” IEEE Trans. Adv. Packag., 26, pp. 152–159. [CrossRef]
Popov, E. P., 1990, Engineering Mechanics of Solids, Prentice–Hall, Englewood Cliffs, NJ.
Behnken, H., Ape1, M., and Franke, D., 2003, “Simulation of Mechanical Stress During Bending Tests for Crystalline Wafers,” 3rd World Conference on Photovoltaic Energy Conversion, Osaka, Japan, May 11–18, pp. 1308–1311.
Misra, A., 2004, “Fracture Simulation for Anisotropic Materials Using a Virtual Internal Bond Model,” Int. J. Solids Struct., 41, pp. 2919–2938. [CrossRef]
Blakers, A. W., and Armour, T., 2009, “Flexible Silicon Solar Cells,” Sol. Energy Mater. Sol. Cells, 93, pp.1440–1443. [CrossRef]
Schneider, A., Rueland, E., Kraenzl, A., and Fath, P., 2004, ‘‘Mechanical and Electrical Characterisation of Thin Multi-Crystalline Silicon Solar Cells,” Proceedings of the 19th European Photovoltaic Solar Energy Conference and Exhibition, Paris, June 7–11.
Richard, W., 1996, Deformation and Fracture Mechanics of Engineering Materials, 4th ed., Wiley & Sons, New York.
Weibull, W. A., 1959, A Statistical Theory of Strength of Materials, Royal Swedish Institute for Engineering Research, Stockholm, Sweden.
Wachtman, J. B., 1996, Mechanical Properties of Ceramics, John Wiley & Sons Inc., New York.
ASTM, 2007, “Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics, C1239-07,” American Society for Testing and Materials, West Conshohocken, PA.
Funke, C., Kullig, E., Kuna, M., and Müller, H. J., 2004, “Biaxial Fracture Test of Silicon Wafers,” Adv. Eng. Mater., 6(7), pp. 594–598. [CrossRef]
Chao, C. C., Chleboski, R., Henderson, E. J., Holmes, C. K., and Kalejs, J. P., 1991, “Fracture Behavior of Silicon Cut With High Power Laser,” Mater. Res. Soc. Symp. Proc., 226, pp. 363–368. [CrossRef]
Chen, C. P., and Leipold, M. H., 1980, “Fracture Toughness of Silicon,” Am. Ceram. Soc. Bull., 59, pp. 469–472.
Grun, A., Lawerenz, A., Porytskyy, R., and Anspach, O., 2011, “Investigation of Wafer Surfaces With Space-Resolved Breaking Strength Tests and Corresponding Analysis of the Crack Depth,” Proceedings of 26th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC), Hamburg, Germany, September 5–9. [CrossRef]
Yang, C., Wu, H., Melkote, S., and Danyluk, S., “Comparative Analysis of Fracture Strength of Slurry and Diamond Wire Sawn Multicrystalline Silicon Solar Wafers,” Adv. Eng. Mater., 15, pp. 358–365. [CrossRef]
Wu, H., Melkote, S. N., and Danyluk, S., 2012, “Mechanical Strength of Silicon Wafers Cut by Loose Abrasive Slurry and Fixed Abrasive Diamond Wire Sawing,” Adv. Eng. Mater., 14, pp. 342–348. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Finite element model for (a) four-point bending (b) twisting

Grahic Jump Location
Fig. 3

Built model from the realistic MC silicon wafer

Grahic Jump Location
Fig. 4

Stress distribution in specimens under (a) von Mises stress for four-point bending and (b) shear stress for twisting

Grahic Jump Location
Fig. 5

J-integral versus time (displacement) for a crack with 1 mm length, 20 μm depth, and zero direction (in parallel direction to the sawing)

Grahic Jump Location
Fig. 6

Material parameters fitted for (a) four point bending and (b) twisting

Grahic Jump Location
Fig. 7

Failure probability versus displacement for (a) four point bending and (b) twisting

Grahic Jump Location
Fig. 8

Probability of existing crack at β = 0 deg for (a) four point bending and (b) twisting loading

Grahic Jump Location
Fig. 9

Probability of existing crack at β = 30 deg for (a) four point bending and (b) twisting loading

Grahic Jump Location
Fig. 10

Probability of existing crack at β = 45 deg for (a) four point bending and (b) twisting loading

Grahic Jump Location
Fig. 11

Probability of existing crack at β = 60 deg for (a) four point bending and (b) twisting loading

Grahic Jump Location
Fig. 12

Probability of existing crack at β = 90 deg for (a) four point bending and (b) twisting loading

Grahic Jump Location
Fig. 13

Crack geometry for the 63% probability of existing crack in wafers

Grahic Jump Location
Fig. 14

Failure probability of stress/force and displacement for (a) four point bending and (b) twisting

Grahic Jump Location
Fig. 15

Frequency distribution versus displacement (a) four point bending for both parallel the sawing and perpendicular to the sawing directions and (b) twisting test for both A and B directions

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In