公开(公告)号：US20220137523A1

公开(公告)日：2022-05-05

申请号：US17432019

申请日：2020-02-06

Applicant: ASML Holding N.V.

Inventor： Joshua ADAMS ,  Yuxiang LIN ,  Krishanu SHOME ,  Gerrit Johannes NIJMEIJER ,  Igor Matheus Petronella AARTS

IPC: G03F9/00

Abstract: An alignment method includes directing an illumination beam with a first polarization state to form a diffracted beam with a second polarization state from an alignment target, and passing the diffracted beam through a polarization analyzer. The alignment method further includes measuring a polarization state of the diffracted beam and determining a location of the alignment target from the measured polarization state relative to its initial polarization state. The alignment target includes a plurality of diffraction gratings with a single pitch and two or more duty cycles, wherein the pitch is smaller than a wavelength of the illumination beam, and the location of the alignment target corresponds to the duty cycle of the diffraction grating.

公开(公告)号：US20180224759A1

公开(公告)日：2018-08-09

申请号：US15746164

申请日：2016-07-19

Applicant: ASML Holding N.V.

Inventor： Krishanu SHOME ,  Justin LIoyd KREUZER

IPC: G03F9/00 ,  G02B5/30 ,  G02B27/09

Abstract: An optical system for improving alignment measurement accuracy is discussed. The optical system includes first and second optical elements. The first optical element may be configured to change a first beam having a first polarization state into a second beam having a second polarization state. The second optical element may be configured to provide total internal reflection of the second beam and to change the second beam into a third beam having a third polarization state. The first, second, and third polarization states may be different from each other.

公开(公告)号：US20220291598A1

公开(公告)日：2022-09-15

申请号：US17770575

申请日：2020-09-28

Applicant: ASML Holding N.V.

Inventor： Krishanu SHOME ,  Igor Petronella AARTS ,  Junwon LEE

IPC: G03F9/00 ,  G01J9/02

Abstract: An apparatus for and method of sensing alignment marks in which a self-referencing interferometer based sensor outputs standing images of the alignment marks and camera device is used to capture the images as output by the sensor and a detector is used to obtain phase information about the alignment marks from the images as output by the sensor.

公开(公告)号：US20220066334A1

公开(公告)日：2022-03-03

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：US20200073255A1

公开(公告)日：2020-03-05

申请号：US16610798

申请日：2018-04-17

Applicant: ASML Holding N.V.

Inventor： Leonardo Gabriel MONTILLA ,  Krishanu SHOME

IPC: G03F7/20

Abstract: A method including illuminating a product test substrate with radiation from a component, wherein the product test substrate does not have a device pattern etched therein and yields a non-zero sensitivity when illuminated, the non-zero sensitivity representing a change in an optical response characteristic of the product test substrate with respect to a change in a characteristic of the radiation; measuring at least a part of the radiation redirected by the product test substrate to determine a parameter value; and taking an action with respect to the component based on the parameter value.

公开(公告)号：US20180299790A1

公开(公告)日：2018-10-18

申请号：US15766427

申请日：2016-10-06

Applicant: ASML Holding N.V.

Inventor： Krishanu SHOME ,  Justin Lloyd KREUZER

IPC: G03F7/20

CPC classification number: G03F7/70566 ,  G03F9/7046 ,  G03F9/7049 ,  G03F9/7065 ,  G03F9/7069 ,  G03F9/7088

Abstract: A metrology system includes a radiation source that generates light, an optical modulation unit, a reflector, an interferometer, and a detector. The optical modulating unit temporally separates a first polarization mode of the light from a second polarization mode of the light. The reflector directs the light towards a substrate. The interferometer interferes the diffracted light from a pattern on the substrate, or reflected light from the substrate, and produces output light from the interference. The detector receives the output light from the interferometer. The first and second polarization modes of the output light are temporally separated at the detector.