公开(公告)号：US09869543B2

公开(公告)日：2018-01-16

申请号：US14184295

申请日：2014-02-19

Applicant: KLA-Tencor Corporation

Inventor： Barak Bringoltz ,  Mark Ghinovker ,  Daniel Kandel ,  Vladimir Levinski ,  Zeev Bomzon

IPC: G01B11/14 ,  G01B11/24

CPC classification number: G01B11/14 ,  G01B11/2441 ,  G03F7/70633

Abstract: Methods and systems for minimizing of algorithmic inaccuracy in scatterometry overlay (SCOL) metrology are provided. SCOL targets are designed to limit the number of oscillation frequencies in a functional dependency of a resulting SCOL signal on the offset and to reduce the effect of higher mode oscillation frequencies. The targets are segmented in a way that prevents constructive interference of high modes with significant amplitudes, and thus avoids the inaccuracy introduced by such terms into the SCOL signal. Computational methods remove residual errors in a semi-empirical iterative process of compensating for the residual errors algorithmically or through changes in target design.