Patent ID: 9018023
Filing Date: 2015-04-28
Classification: H01L

Abstract:
1. A method comprising: forming a metal pattern on each of a plurality of wafers; polishing each wafer; for each wafer, determining the endpoint of polishing by: periodically measuring the reflectance of the wafer surface during polishing; and receiving an optical across-wafer endpoint signal when the reflectance reaches a predetermined level; analyzing the surface of the metal pattern on each polished wafer for the presence of defects in the metal pattern by analyzing the optical across-wafer endpoint signal, generated at the endpoint of polishing; repeating the steps of polishing each wafer, determining the endpoint of polishing, and analyzing the surface of the metal pattern on each polished wafer for defects, for each subsequent wafer of the plurality of wafers until a defect is detected; and stopping polishing of the remaining wafers of the plurality of wafers once a defect is detected.