US 12,293,915 B2
Diamond wafer dividing method and chip manufacturing method
Yoshiaki Shimizu, Tokyo (JP)
Assigned to DISCO CORPORATION, Tokyo (JP)
Filed by DISCO CORPORATION, Tokyo (JP)
Filed on Aug. 22, 2022, as Appl. No. 17/821,347.
Claims priority of application No. 2021-143683 (JP), filed on Sep. 3, 2021.
Prior Publication US 2023/0071868 A1, Mar. 9, 2023
Int. Cl. H01L 21/268 (2006.01); B23K 26/50 (2014.01); B23K 103/00 (2006.01)
CPC H01L 21/268 (2013.01) [B23K 26/50 (2015.10); B23K 2103/56 (2018.08)] 8 Claims
OG exemplary drawing
 
1. A diamond wafer dividing method used when a diamond wafer having a front surface along a {100} plane is divided at planned dividing lines along a <110> direction, the dividing method comprising:
a first modified layer forming step of forming a first modified layer at a linear first region along the planned dividing line, inside the diamond wafer by executing irradiation with a laser beam with such a wavelength as to be transmitted through the diamond wafer, in such a manner that the laser beam is focused on the first region;
a second modified layer forming step of forming a second modified layer at a linear second region that is shifted from the first region in a width direction which is parallel to the front surface and which is perpendicular to the first region and in a thickness direction perpendicular to the front surface and that is inside the diamond wafer, by executing irradiation with the laser beam with such a wavelength as to be transmitted through the diamond wafer, in such a manner that the laser beam is focused on the second region; and
a dividing step of dividing the diamond wafer along the planned dividing lines by giving a force to the diamond wafer in which the first modified layer and the second modified layer are formed.