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Fracture Behavior of Silicon Cut with a High Power Laser

Published online by Cambridge University Press:  26 February 2011

C.C. Chao ,
R. Chleboski ,
E.J. Henderson ,
C.K. Holmes ,
J.P. Kalejs  and
T.S. Gross
C.C. Chao
Affiliation:
Mobil Solar Energy Corporation, Billerica MA 01821
R. Chleboski
Affiliation:
Mobil Solar Energy Corporation, Billerica MA 01821
E.J. Henderson
Affiliation:
Mobil Solar Energy Corporation, Billerica MA 01821
C.K. Holmes
Affiliation:
Mobil Solar Energy Corporation, Billerica MA 01821
J.P. Kalejs
Affiliation:
Mobil Solar Energy Corporation, Billerica MA 01821
T.S. Gross
Affiliation:
Department of Mechanical Engineering, University of New Hampshire, Durham, NH 03824
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Abstract

The fracture twist test is used to obtain the statistical fracture strength distribution for 10-cm square single crystal and polycrystalline silicon wafers cut with a high-power Nd:YAG laser. Tensile wafer edge stresses at fracture are calculated using nonlinear finite element analysis, and the model results are used to examine the limitations of linear torsion and plate theories. The basic hypothesis is that fracture strength of laser-cut wafers is limited by microcracks formed by large residual tensile stresses produced in the cut edge upon cooling after cutting. Differences are found between single crystal CZ and polycrystalline EFG silicon material Weibull parameters characterizing the fracture strength distribution. These indicate that there is a statistical influence of material variables on the fracture strength of the EFG silicon, which lowers its strength and increases the variance of fracture response in comparison to single crystal silicon.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 226: Symposium H – Mechanical Behavior of Materials and Structures in Microelectronics , 1991 , 363
Copyright
Copyright © Materials Research Society 1991

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References

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