公开(公告)号：US11493852B2

公开(公告)日：2022-11-08

申请号：US17415711

申请日：2019-12-12

Applicant: ASML Holding N.V.

Inventor： Zahrasadat Dastouri ,  Greger Göte Andersson ,  Krishanu Shome ,  Igor Matheus Petronella Aarts

IPC: G03F9/00

Abstract: A method of applying a measurement correction includes determining an orthogonal subspace used to characterize the measurement as a plot of data. A first axis of the orthogonal subspace corresponds to constructive interference output from an interferometer of the metrology system plus a first error variable and a second axis of the orthogonal subspace corresponds to destructive interference output from the interferometer of the metrology system plus a second error variable. The method also includes determining a slope of the plot of data and determining a fitted line to the plot of data in the orthogonal subspace based on the slope.

公开(公告)号：US11513446B2

公开(公告)日：2022-11-29

申请号：US17297691

申请日：2019-11-26

Applicant: ASML Holding N.V.

Inventor： Greger Göte Andersson ,  Krishanu Shome ,  Zahrasadat Dastouri ,  Igor Matheus Petronella Aarts

IPC: G03F9/00 ,  G03F7/20

Abstract: A method of applying a measurement correction includes determining an orthogonal subspace used to characterize a first principal component of the measurement and a second principal component of the measurement, and rotating the orthogonal subspace by a first angle such that the first principle component rotates to become a first factor vector and the second principle component rotates to become a second factor vector. An asymmetry vector is generated by rotating the second factor vector by a second angle, where the asymmetry vector and the first factor vector define a non-orthogonal subspace. An asymmetry contribution is determined in the measurement based on the projection of the measurement onto the first factor vector in the non-orthogonal subspace. The method also includes subtracting the asymmetry contribution from the measurement.

公开(公告)号：US20210397103A1

公开(公告)日：2021-12-23

申请号：US17297691

申请日：2019-11-26

Applicant: ASML Holding N.V.

Inventor： Greger Göte Andersson ,  Krishanu Shome ,  Zahrasadat Dastouri ,  Igor Matheus Petronella Aarts

IPC: G03F9/00 ,  G03F7/20

Abstract: A method of applying a measurement correction includes determining an orthogonal subspace used to characterize a first principal component of the measurement and a second principal component of the measurement, and rotating the orthogonal subspace by a first angle such that the first principle component rotates to become a first factor vector and the second principle component rotates to become a second factor vector. An asymmetry vector is generated by rotating the second factor vector by a second angle, where the asymmetry vector and the first factor vector define a non-orthogonal subspace. An asymmetry contribution is determined in the measurement based on the projection of the measurement onto the first factor vector in the non-orthogonal subspace. The method also includes subtracting the asymmetry contribution from the measurement.