Patent ID: 11901171
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Machine tools (Mechanical engineering)
Classification: CPC H  B | IPC B  H

Claim 8:
9. A method comprising:
bonding a second wafer to a first wafer;
aligning a stealth laser apparatus over the second wafer using alignment marks on the first wafer;
using the stealth laser apparatus to form a stealth damage region that separates an inner region of the second wafer from an outer region of the second wafer, wherein the stealth damage region is arranged at a first distance from an outer perimeter of the second wafer, and wherein the stealth damage region extends from a first depth beneath a top surface of the second wafer to a second depth beneath the top surface of the second wafer;
aligning a blade over the second wafer;
removing the outer region of the second wafer using the blade; and
removing a top portion of the inner region of the second wafer.