A method of cutting an object along two different directions using elliptically polarised laser beam

摘要

The present application relates to a method of cutting a work (1) without producing a fusing and a cracking out of a predetermined cutting line on the surface of the work (1), wherein a pulse laser beam is radiated on a first predetermined cut line (5) on the surface (3) of the work (1) under the conditions causing a multiple photon absorption and with a condensed point aligned to the inside of the work (1), and a modified area is formed inside the work (1) along the predetermined determined cut line (5) by moving the condensed point (P) along the predetermined cut line (5), whereby the work (1) can be cut with a rather small force by cracking the work (1) along the predetermined cut line (5) starting from the modified area and, because the pulse laser beam radiated is not almost absorbed onto the surface (3) of the work (1), the surface (3) is not fused even if the modified area is formed. The pulse laser beam (L) is then radiated on a second predetermined cut line (5) extending in a second different direction. The laser light is also eliptically polarized (LP).