Anisotropy of Fracture Strength and Fracture Toughness of Micro-Sized Single-Crystal Silicon

Abstract

This paper presents the dependence of fracture toughness, fracture strength, and fracture behavior, such as crack propagation, on the crystal orientation of single-crystal silicon. We conducted on-chip tensile testing to measure fracture strength and fracture toughness of single-crystal silicon films with (100) and (110) surface in the <100> and <110> loading direction. The loading direction had a significant effect on fracture toughness, which was 2.17MPa√m in the <100> direction and 1.27MPa√m in <110>. However, the fracture strength varies with both loading direction and surface orientation. We observed a fracture specimen on which a (111) cleavage plane eventually appeared on any crystal types of the specimen.