公开(公告)号：US11243470B2

公开(公告)日：2022-02-08

申请号：US16331547

申请日：2017-08-21

Applicant: ASML NETHERLANDS B.V.

Inventor： Nitish Kumar ,  Adrianus Johannes Hendrikus Schellekens ,  Sietse Thijmen Van Der Post ,  Ferry Zijp ,  Willem Maria Julia Marcel Coene ,  Peter Danny Van Voorst ,  Duygu Akbulut ,  Sarathi Roy

IPC: G03F7/20

Abstract: An optical system delivers illuminating radiation and collects radiation after interaction with a target structure on a substrate. A measurement intensity profile is used to calculate a measurement of the property of the structure. The optical system may include a solid immersion lens. In a method, the optical system is controlled to obtain a first intensity profile using a first illumination profile and a second intensity profile using a second illumination profile. The profiles are used to derive a correction for mitigating the effect of, e.g., ghost reflections. Using, e.g., half-moon illumination profiles in different orientations, the method can measure ghost reflections even where a solid immersion lens would cause total internal reflection. The optical system may include a contaminant detection system to control a movement based on received scattered detection radiation. The optical system may include an optical component having a dielectric coating to enhance evanescent wave interaction.

公开(公告)号：US10725381B2

公开(公告)日：2020-07-28

申请号：US16117589

申请日：2018-08-30

Applicant: ASML Netherlands B.V.

Inventor： Sietse Thijmen Van Der Post ,  Stefan Michael Bruno Bäumer ,  Peter Danny Van Voorst ,  Teunis Willem Tukker ,  Ferry Zijp ,  Han-Kwang Nienhuys ,  Jacobus Maria Antonius Van Den Eerenbeemd

IPC: G21K1/00 ,  G03F7/20 ,  G21K7/00 ,  G21K1/06 ,  G02B17/04 ,  G01N21/47 ,  G01N21/95

Abstract: An optical system (OS) for focusing a beam of radiation (B) on a region of interest in a metrology apparatus is described. The beam of radiation (B) comprises radiation in a soft X-ray or Extreme Ultraviolet spectral range. The optical system (OS) comprises a first stage (S1) for focusing the beam of radiation at an intermediate focus region. The optical system (OS) comprises a second stage (S2) for focusing the beam of radiation from the intermediate focus region onto the region of interest. The first and second stages each comprise a Kirkpatrick-Baez reflector combination. At least one reflector comprises an aberration-correcting reflector.

公开(公告)号：US10712673B2

公开(公告)日：2020-07-14

申请号：US16331601

申请日：2017-08-17

Applicant: ASML NETHERLANDS B.V.

Inventor： Sietse Thijmen Van Der Post ,  Koos Van Berkel

IPC: G03F7/20 ,  G01N21/956

Abstract: An optical system and detector capture a distribution of radiation modified by interaction with a target structure. The observed distribution is used to calculate a property of the structure (e.g. CD or overlay). A condition error (e.g. focus error) associated with the optical system is variable between observations. The actual condition error specific to each capture is recorded and used to apply a correction for a deviation of the observed distribution due to the condition error specific to the observation. The correction in one practical example is based on a unit correction previously defined with respect to a unit focus error. This unit correction can be scaled linearly, in accordance with a focus error specific to the observation.

公开(公告)号：US10451559B2

公开(公告)日：2019-10-22

申请号：US16102178

申请日：2018-08-13

Applicant: ASML Netherlands B.V.

Inventor： Peter Danny Van Voorst ,  Nan Lin ,  Sander Bas Roobol ,  Simon Gijsbert Josephus Mathijssen ,  Sietse Thijmen Van Der Post

IPC: G01N21/88 ,  G03F7/20 ,  G01N21/95 ,  H05G2/00 ,  G01N21/956

Abstract: Disclosed is an inspection apparatus and associated method for measuring a target structure on a substrate. The inspection apparatus comprises an illumination source for generating measurement radiation; an optical arrangement for focusing the measurement radiation onto said target structure; and a compensatory optical device. The compensatory optical device may comprise an SLM operable to spatially modulate the wavefront of the measurement radiation so as to compensate for a non-uniform manufacturing defect in said optical arrangement. In alternative embodiments, the compensatory optical device may be located in the beam of measurement radiation, or in the beam of pump radiation used to generate high harmonic radiation in a HHG source. Where located in the beam of pump radiation, the compensatory optical device may be used to correct pointing errors, or impart a desired profile or varying illumination pattern in a beam of the measurement radiation.

公开(公告)号：US10248029B2

公开(公告)日：2019-04-02

申请号：US15580500

申请日：2016-07-05

Applicant: ASML Netherlands B.V.

Inventor： Sietse Thijmen Van Der Post ,  Ferry Zijp ,  Sander Bas Roobol

IPC: G03B27/54 ,  G03F7/20

Abstract: A method involving a radiation intensity distribution for a target measured using an optical component at a gap from the target, the method including: determining a value of a parameter of interest using the measured radiation intensity distribution and a mathematical model describing the target, the model including an effective medium approximation for roughness of a surface of the optical component or a part thereof.