Patent ID: 8673167
Filing Date: 2014-03-18
Classification: B23K,B81B,B81C,H01L

Abstract:
1. A laser processing method for forming a hole in a sheet-like object to be processed made of silicon, the method comprising: a depression forming step of forming a depression in a part corresponding to the hole on a laser light entrance surface side of the object, the depression opening to the laser light entrance surface; a modified region forming step of forming a modified region along a part corresponding to the hole in the object by converging a laser light at the object after the depression forming step, the modified region being formed by a plurality of modified spots; and an etching step of anisotropically etching the object after the modified region forming step so as to advance the etching selectively along the modified region and form the hole in the object; wherein the modified region forming step exposes the modified region or a fracture extending from the modified region to an inner face of the depression.