Method and Apparatus for Extracting Systematic Defects

摘要

The present disclosure provides a method of systematic defect extraction. Primary and secondary areas are defined in a wafer layout. A plurality of defects is identified by a first wafer inspection for an outside-process-window wafer. Defects located in the secondary area are removed. Defects associated with non-critical semiconductor features are also removed via a grouping process. Sensitive regions are defined around defects associated with critical semiconductor features. A second inspection is then performed on the sensitive regions for an inside-process-window wafer, thereby identifying a plurality of potentially systematic defects. Thereafter, a Scanning Electron Microscopy (SEM) process is performed to determine whether the defects in the sensitive regions of the inside-process-window wafer are true systematic defects.

主权项

1. A method, comprising:
defining a primary area and a secondary area in a wafer layout; identifying a plurality of defects by performing a first inspection on the primary area and the secondary area for an outside-process-window wafer; performing a first nuisance defect filtering process by removing the defects in the secondary area; thereafter performing a grouping process to the defects outside the secondary area to separate the defects into a plurality of groups, wherein the defects that are grouped together have substantially similar characteristics; determining one or more groups of the defects that are associated with non-critical semiconductor features; performing a second nuisance defect filtering process by removing the one or more groups of the defects that are associated with non-critical semiconductor features; thereafter defining localized regions around remaining groups of the defects on the wafer layout; thereafter performing a second inspection on the localized regions for an inside-process-window wafer, thereby identifying a plurality of potentially systematic defects; and visually examining each of the defects in the localized regions of the inside-process-window wafer to ascertain a list of systematic defects.