LASER PROCESSING METHOD AND DEVICE

摘要

A laser processing method which can efficiently perform laser processing while minimizing the deviation of the converging point of a laser beam in end parts of an object to be processed is provided. This laser processing method comprises a preparatory step of holding a lens at an initial position set such that a converging point is located at a predetermined position within the object; a first processing step (S11 and S12) of emitting a first laser beam for processing while holding the lens at the initial position, and moving the lens and the object relative to each other along a main surface so as to form a modified region in one end part of a line to cut; and a second processing step (S13 and S14) of releasing the lens from being held at the initial position after forming the modified region in the one end part of the line to cut, and then moving the lens and the object relative to each other along the main surface while adjusting the gap between the lens and the main surface after the release, so as to form the modified region.