Patent ID: 7211526

Claim:
A method for manufacturing a segment from an object, said method comprising: a preparing step of preparing the object which has a crystalline structure; a surface processing step of processing the object by forming a recessed portion in a surface of the object, the recessed portion being effective to cause a stress concentration at the surface of the object; an internal processed-region forming step of forming an internal processed-regions at a depth of the object in a line along which a laser beam scans the surface of the object by a relative motion therebetween, the laser beam being converged adjacent the depth, wherein the thus formed internal processed-regions extend in a direction substantially perpendicular to the surface of the object; and an external force applying step of applying an external force to the object to form a crack between the recessed portion and the internal processed-regions, the crack extending along a non-cleavage plane of the crystalline structure.