公开(公告)号：SG11202001694XA

公开(公告)日：2020-07-29

申请号：SG11202001694X

申请日：2018-12-10

Applicant: KLA TENCOR CORP

Inventor： GUTMAN NADAV ,  AMIT ERAN ,  EYRING STEFAN ,  PATHANGI SRIRAMAN HARI ,  LASKE FRANK ,  POHLMANN ULRICH ,  HEIDRICH THOMAS

IPC: G03F7/20 ,  G01N21/84 ,  H01L21/66 ,  H01L21/67

Abstract: An overlay metrology system includes a particle-beam metrology tool to scan a particle beam across an overlay target on a sample including a first-layer target element and a second-layer target element. The overlay metrology system may further include a controller to receive a scan signal from the particle-beam metrology tool, determine symmetry measurements for the scan signal with respect to symmetry metrics, and generate an overlay measurement between the first layer and the second layer based on the symmetry measurements in which an asymmetry of the scan signal is indicative of a misalignment of the second-layer target element with respect to the first-layer target element and a value of the overlay measurement is based on the symmetry measurements.