Premium
Mechanical Strength of Silicon Wafers Cut by Loose Abrasive Slurry and Fixed Abrasive Diamond Wire Sawing
Author(s) -
Wu Hao,
Melkote Shreyes N.,
Danyluk Steven
Publication year - 2012
Publication title -
advanced engineering materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.938
H-Index - 114
eISSN - 1527-2648
pISSN - 1438-1656
DOI - 10.1002/adem.201100263
Subject(s) - materials science , abrasive , wafer , diamond , composite material , flexural strength , bending , fracture mechanics , enhanced data rates for gsm evolution , slurry , fracture (geology) , silicon , metallurgy , telecommunications , computer science , nanotechnology
This paper reports on the mechanical strength of polycrystalline silicon wafers cut by loose abrasive slurry and fixed abrasive diamond wire sawing processes. Four line bending and biaxial flexure tests are used to evaluate the fracture strength of the wafers. Fracture strength of the wafers depends on the location, size, and orientation of microcracks in the silicon wafer and the distribution and magnitude of applied stresses. Measurement of microcracks at the wafer edge and center shows that edge cracks are typically larger than center cracks. Fixed abrasive diamond wire sawn wafers are found to have a higher crack density but smaller average crack length. Wafer fracture in four line bending is found to be primarily due to the propagation of edge cracks while center cracks are found to be the primary cause of wafer failure in biaxial flexure tests. Fracture mechanics based analyses demonstrate that crack orientation plays a significant role in four line bending, but not in biaxial flexure. Correlations of the wafer fracture strength and critical crack length agree well with microcrack measurements. The fracture strength of diamond cut wafers is found to be comparable or superior to the strength of slurry cut wafers.