公开(公告)号：US20170248852A1

公开(公告)日：2017-08-31

申请号：US15438364

申请日：2017-02-21

Applicant: ASML Netherlands B.V.

Inventor： Patrick WARNAAR ,  Simon Philip Spencer HASTINGS ,  Alberto DA COSTA ASSAFRAO ,  Lukasz Jerzy MACHT

IPC: G03F7/20

Abstract: An inspection apparatus (140) measures asymmetry or other property of target structures (T) formed by a lithographic process on a substrate. For a given set of illumination conditions, accuracy of said measurement is influenced strongly by process variations across the substrate and/or between substrates. The apparatus is arranged to collect radiation scattered by a plurality of structures under two or more variants of said illumination conditions (p1−, p1, p1+; λ1−, λ1, λ1+). A processing system (PU) is arranged to derive the measurement of said property using radiation collected under a different selection or combination of said variants for different ones of said structures. The variants may be for example in wavelength, or in angular distribution, or in any characteristic of the illumination conditions. Selection and/or combination of variants is made with reference to a signal quality (302, Q, A) observed in the different variants.

公开(公告)号：US20190250520A1

公开(公告)日：2019-08-15

申请号：US16393055

申请日：2019-04-24

Applicant: ASML Netherlands B.V.

Inventor： Adam Jan URBANCZYK ,  Hans VAN DER LAAN ,  Grzegorz GRZELA ,  Alberto DA COSTA ASSAFRAO ,  Chien-Hung TSENG ,  Jay Jianhui CHEN

IPC: G03F7/20 ,  G01N21/47

Abstract: Disclosed is a process monitoring method, and an associated metrology apparatus. The method comprises: obtaining measured target response sequence data relating to a measurement response of a target formed on a substrate by a lithographic process to measurement radiation comprising multiple measurement profiles, wherein the measured target response sequence data describes a variation of the measurement response of the target in response to variations of the measurement profiles; obtaining reference target response sequence data relating to a measurement response of the target as designed to the measurement radiation, wherein the reference target response sequence data describes an optimal measurement response of the target in response to designed measurement profiles without un-designed variation; comparing the measured target response sequence data and the reference target response sequence data; and determining values for variations in stack parameters of the target from the measured target response sequence data based on the comparison.