US 11,911,842 B2
Laser-assisted method for parting crystalline material
Matthew Donofrio, Raleigh, NC (US); John Edmond, Durham, NC (US); Harshad Golakia, Morrisville, NC (US); and Eric Mayer, Raleigh, NC (US)
Assigned to WOLFSPEED, INC., Durham, NC (US)
Filed by Wolfspeed, Inc., Durham, NC (US)
Filed on Jan. 10, 2022, as Appl. No. 17/572,137.
Application 17/572,137 is a continuation of application No. 16/792,261, filed on Feb. 16, 2020, granted, now 11,219,966.
Application 16/792,261 is a continuation of application No. 16/410,487, filed on May 13, 2019, granted, now 10,562,130, issued on Feb. 18, 2020.
Application 16/410,487 is a continuation in part of application No. 16/274,064, filed on Feb. 12, 2019, granted, now 10,576,585, issued on Mar. 3, 2020.
Claims priority of provisional application 62/803,340, filed on Feb. 8, 2019.
Claims priority of provisional application 62/786,333, filed on Dec. 29, 2018.
Prior Publication US 2022/0126395 A1, Apr. 28, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. B23K 26/03 (2006.01); H01L 21/02 (2006.01); B28D 5/00 (2006.01); B23K 26/53 (2014.01); B23K 26/40 (2014.01)
CPC B23K 26/032 (2013.01) [B23K 26/40 (2013.01); B23K 26/53 (2015.10); B28D 5/0064 (2013.01); H01L 21/02686 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A crystalline material processing method comprising:
supplying emissions of a laser focused along a first average depth position within an interior of a crystalline material of a substrate, and effecting relative lateral movement between the laser and the substrate, to form subsurface laser damage having at least one subsurface laser damage pattern;
following formation of the at least one subsurface laser damage pattern, generating at least one image of a top surface of the substrate;
analyzing the at least one image to identify a condition indicative of presence of uncracked regions in the interior of the substrate; and
responsive to the analyzing, performing at least one of the following steps (i) or (ii):
(i) effecting relative movement between the laser and the substrate while supplying emissions of the laser focused within the interior of the substrate in at least the uncracked regions to form supplemental subsurface laser damage to supplement the at least one subsurface laser damage pattern along or proximate to the first average depth position, for formation of a first reduced thickness portion of the substrate;
(ii) changing an instruction set, associated with the substrate, for forming subsurface laser damage when producing subsurface laser damage patterns at a second average depth position, for formation of at least one additional reduced thickness portion of the substrate.