| 摘要 |
The disclosed laser processing method includes: a laser-light focusing step in which laser light (L) is focused on a flat target object (1) formed from silicon, thereby forming modified regions (71 to 73) inside the target object (1); and an etching treatment step, after the laser-light focusing step, in which the target object (1) is anisotropically etched, said etching acting to reduce the thickness of the target object (1) to a target thickness and made to selectively progress along the modified regions (71 to 73) to form through-holes (24), angled with respect to the thickness direction of the target object (1), inside the target object (1). In the laser-light focusing step, first modified regions (72) and second modified regions (71 and 73) are formed. Said first modified regions are formed in parts of the target object (1) that correspond to the through-holes (24), and said second modified regions connect to the first modified regions (72) and extend in a parallel manner, in the thickness direction, to the parts of the target object (1) which are removed as the thickness of the target object is decreased by anisotropic etching. In the etching treatment step, as the thickness of the target object (1) is decreased, the etching is made to selectively progress along the second modified regions (71 and 73) and then the first modified regions (72), completing the formation of the through-holes (24) when the target object (1) has reached the target thickness. |
