Rationale: Bonded wafer stack (BWS) thickness, total thickness variation (TTV), bow, warp/sori, and flatness metrology is essential before, during, and after the wafer bonding process. These parameters provide meaningful information about the quality of the wafer thinning process (if used), the uniformity of the bonding process, and the amount of bow and warp/sori induced on the wafer stack by the bonding process. The quality of lithography is also dependent on having uniformly flat wafers. Total thickness variation is also critical in bonded wafer manufacturing, since intermittent TSV contact to M2 will occur due to non-planarity. Non-planarity may also affect overlay quality. Subsequently this study can assist producers and users of other wafer bonding processes to develop robust products and conduct meaningful substrate evaluations.
NOW! BALLOT PASSED and APPROVED AT THE SEMI 2013 SPRING STANDARDS MEETINGS
Key Contact: Victor Vartanian