Patent ID: 11911842
Assignee: WOLFSPEED, INC.
Field: Machine tools (Mechanical engineering)
Classification: CPC B  C  H | IPC B  H

Claim 8:
9. A crystalline material processing method comprising:
supplying laser emissions focused within an interior of a crystalline material of a substrate, and effecting relative lateral movement between the laser and the substrate, to form a first pattern of subsurface laser damage sites distributed among non-overlapping first and second areas of the substrate;
supplying laser emissions focused within the interior of the crystalline material of the substrate, and effecting relative lateral movement between the laser and the substrate, to form a second pattern of subsurface laser damage sites distributed among the non-overlapping first and second areas of the substrate, wherein at least some subsurface laser damage sites of the second pattern of subsurface laser damage sites do not cross subsurface laser damage sites of the first pattern of subsurface laser damage sites;
detecting presence of a condition indicative of non-uniform doping of the crystalline material across at least a portion of a surface of the substrate, the non-uniform doping including at least one first doping region and at least one second doping region; and
responsive to detection of the condition indicative of non-uniform doping of the crystalline material, altering laser power to provide laser emissions at a first average power when forming subsurface laser damage in a first doping region and provide laser emissions at a second average power that differs from the first average power when forming subsurface laser damage in a second doping region, during formation of the first pattern of subsurface laser damage sites and the second pattern of subsurface laser damage sites.