Patent ID: 8431467

Claim:
A method for manufacturing a microchip by irradiating an object to be processed, which made of crystalline material and including a plurality of functional devices, with laser light while locating a converging point of the laser light within the object, so as to form a modified region serving as a cutting start point within the object along a cutting line, the method comprising; forming a first modified region within the object and generating a first fracture inside of the object from the first modified region, the first fracture extending in a direction tilted with respect to a plane extending in the thickness direction and cutting line; forming a second modified region within the object and generating a second fracture inside of the object from the second modified region, the second fracture extending in a direction tilted with respect to the plane so as to connect with the second fracture with the first fracture; and cutting the object along the cutting line from the first and second modified regions by using each of the first and second modified regions as a cutting start region to thereby form an irregular cut section along the first and second fractures as viewed from a side of the object in a direction of the cutting line.