Study on cleaving mechanism of silicon wafer by laser beam irradiation

Abstract

Laser cleaving is used as a technique to separate a thin plate of brittle materials. In this paper, the influence of crystal orientation on crack propagation is investigated experimentally. As a workpiece, a (100) face silicon wafer is used. The pre-crack induced by a Vickers indenter is observed with an optical microscope. Additionally, laser cleaving along the semicircle is performed. The results show the crack propagation with laser cleaving is along the cleavage plane. When the crack propagates along a direction of cleavage plane, the roughness of the fracture surface is very small. When the crack propagates along the direction between two cleavage planes, the fracture surface has the periodic wave.