Patents by Inventor Leonard Wai Fung Kho

Leonard Wai Fung Kho has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20150036113
    Abstract: An immersion lithography system and method exposes a substrate through a liquid. The substrate is exposed through the liquid, which is provided between a final optical element of a projection lens and the substrate. The liquid is recovered from an upper surface of the substrate via a recovery opening of an immersion apparatus under which the substrate is positioned, the immersion apparatus being disposed around the final optical element of the projection lens. The a pressure for recovering the liquid from the upper surface of the substrate via the recovery opening is controlled by a pressure control system, the pressure control system having a first tank connected to the recovery opening via a recovery flow line and a vacuum regulator to control a pressure in the first tank.
    Type: Application
    Filed: October 21, 2014
    Publication date: February 5, 2015
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO
  • Patent number: 8934080
    Abstract: An immersion lithography apparatus includes a projection system having a final optical element, a movable stage that is movable below the projection system such that a gap exists between the final optical element and a surface of the stage, an immersion liquid being filled in the gap, a liquid confinement member and a liquid diverter. The liquid confinement member maintains the immersion liquid in the gap, and includes a liquid recovery portion that faces the stage surface and recovers liquid from the gap. The liquid recovery portion includes a first porous portion through which a first suction force is applied and a second porous portion through which a second suction force less than the first suction force is applied, the second portion being located outward of the first portion. The liquid diverter is positioned between the stage and at least the first porous portion.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: January 13, 2015
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Derek Coon, Gaurav Keswani
  • Patent number: 8896807
    Abstract: A liquid immersion lithography apparatus includes a projection system having a final optical element via which a substrate is exposed to an exposure beam through an immersion liquid located between the final optical element and the substrate, and a nozzle member. The nozzle member has a first opening on one side of the final optical element and from which the immersion liquid is supplied, a second opening on a second side of the final optical element and from which the immersion liquid is collected, and a liquid recovery portion that surrounds a path of the exposure beam and from which the immersion liquid is collected. During exposure, an upper surface of the substrate faces the liquid recovery portion, and the immersion liquid is supplied from the first opening while the immersion liquid supplied from the first opening is recovered from the second opening and the liquid recovery portion.
    Type: Grant
    Filed: July 17, 2013
    Date of Patent: November 25, 2014
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho
  • Publication number: 20140232999
    Abstract: A lithographic projection apparatus includes a stage assembly having a substrate table on which a substrate is supported and exposed with an exposure beam from a final optical element of a projection optical assembly through an immersion liquid. A confinement member encircles a portion of a path of the exposure beam and has an aperture through which the exposure beam is projected. A movable member is movable in a space between the confinement member and the substrate, the substrate table, or both, such that a first portion of the space is located between a first surface of the movable member and the confinement member, and a second portion of the space is located between a second surface of the movable member and the substrate, the substrate table, or both.
    Type: Application
    Filed: April 25, 2014
    Publication date: August 21, 2014
    Applicant: NIKON CORPORATION
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO, Gaurav KESWANI, Derek COON, Daishi TANAKA
  • Patent number: 8780323
    Abstract: Immersion fluid remaining on a portion of a substrate after that portion has passed an immersion nozzle is removed by moving the substrate relative to an immersion nozzle so that the portion of the substrate on which the immersion fluid remains is passed by the immersion nozzle again. A path is determined along which the substrate is to be moved to remove the remaining immersion fluid. The path can be determined based upon previous movements of the substrate, including factors such as the speed and/or length of the previous movements. Alternatively, portions of the substrate on which immersion fluid remains can be detected, and then the substrate can be moved so that the portion of the substrate on which the immersion fluid remains is passed by the immersion nozzle based on the results of the detection. Immersion fluid also can be removed from the stage surface located beyond the substrate.
    Type: Grant
    Filed: March 11, 2011
    Date of Patent: July 15, 2014
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Gaurav Keswani
  • Patent number: 8743343
    Abstract: A lithographic projection apparatus includes a projection optical assembly having a final optical element, a stage assembly including a substrate table on which a substrate is supported, the substrate supported by the substrate table being exposed with an exposure beam from the final optical element of the projection optical assembly through an immersion liquid, a confinement member which encircles a portion of a path of the exposure beam, and a movable member which is movable in a space between the confinement member and the substrate, the substrate table, or both, the space being divided by the movable member into a first portion between the confinement member and the movable member and a second portion between the movable member and the substrate, the substrate table, or both. The movable member has a recovery outlet from which the immersion liquid in the second portion is removed.
    Type: Grant
    Filed: January 30, 2013
    Date of Patent: June 3, 2014
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Gaurav Keswani, Derek Coon, Daishi Tanaka
  • Publication number: 20140071412
    Abstract: An immersion lithography apparatus that includes a substrate holder on which a substrate is held, a projection system having a final optical element and that projects an exposure beam onto the substrate through an immersion liquid, and a liquid confinement member having an aperture through which the exposure beam is projected, a lower surface including a non-fluid removal area surrounding the aperture, and a liquid recovery outlet from which the immersion liquid is recovered, also includes a movable member. The movable member is movable relative to the liquid confinement member in a substantially horizontal direction, and has an opening through which the exposure beam is projected. The movable member has upper and lower surfaces that surround the opening, and is movable while a portion of the upper surface faces the non-fluid removal area in the lower surface of the liquid confinement member.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 13, 2014
    Applicant: NIKON CORPORATION
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO, Derek COON, Gaurav KESWANI, Daishi TANAKA
  • Patent number: 8634055
    Abstract: An immersion liquid confinement apparatus recovers an immersion liquid from an immersion area that includes a gap between a projection system and an object of exposure in an immersion lithography system. The apparatus includes a confinement member that includes an outlet and an aperture through which a patterned image is projected onto the object. A first liquid-permeable member covers the outlet and has a first surface that faces the object and a second surface opposite the first surface, the second surface contacting a first chamber. A second liquid-permeable member has first and second oppositely-facing surfaces, the first surface of the second liquid-permeable member contacts the first chamber, the second surface of the second liquid-permeable member contacts a second chamber that is different from the first chamber. A hydrophobic porous member is provided between the first chamber and a vacuum system that supplies a low pressure to the first chamber.
    Type: Grant
    Filed: February 2, 2010
    Date of Patent: January 21, 2014
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Derek Coon, Gaurav Keswani
  • Patent number: 8610873
    Abstract: An immersion lithography apparatus includes a projection system having a final optical element and a stage that is movable to a position below the projection system such that a gap exists between the final optical element and a surface of the stage. An immersion liquid fills the gap between the surface and the final optical element. A liquid confinement member maintains the immersion liquid in the gap. The immersion liquid has a meniscus where the liquid contacts ambient gas, the meniscus defining a footprint of an immersion area. A movable liquid diverter is positioned between the liquid confinement member and the stage. The movable liquid diverter moves relative to the liquid confinement member in a direction parallel to the surface of the stage, and includes an opening that surrounds the immersion area, the opening contacting or being slightly spaced from the immersion area when the stage is stationary.
    Type: Grant
    Filed: March 9, 2009
    Date of Patent: December 17, 2013
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Derek Coon, Gaurav Keswani, Daishi Tanaka
  • Publication number: 20130301015
    Abstract: A liquid immersion lithography apparatus includes a projection system having a final optical element via which a substrate is exposed to an exposure beam through an immersion liquid located between the final optical element and the substrate, and a nozzle member. The nozzle member has a first opening on one side of the final optical element and from which the immersion liquid is supplied, a second opening on a second side of the final optical element and from which the immersion liquid is collected, and a liquid recovery portion that surrounds a path of the exposure beam and from which the immersion liquid is collected. During exposure, an upper surface of the substrate faces the liquid recovery portion, and the immersion liquid is supplied from the first opening while the immersion liquid supplied from the first opening is recovered from the second opening and the liquid recovery portion.
    Type: Application
    Filed: July 17, 2013
    Publication date: November 14, 2013
    Applicant: Nikon Corporation
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO
  • Publication number: 20130286366
    Abstract: An immersion liquid confinement apparatus confines an immersion liquid in an immersion area that includes a gap between a projection system and an object of exposure in an immersion lithography system. The apparatus also recovers the immersion liquid from the immersion area. The apparatus includes an aperture through which a patterned image is projected, an outlet, a first chamber into which the immersion liquid is recovered through the outlet, and a second chamber into which the immersion liquid is recovered through a porous member from the first chamber. The porous member has a first surface contacting the first chamber and a second surface contacting the second chamber. A vertical position of a first portion of the first surface is different from a vertical position of a second portion of the first surface.
    Type: Application
    Filed: June 27, 2013
    Publication date: October 31, 2013
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO, Derek COON
  • Patent number: 8520187
    Abstract: A lithographic projection apparatus projects a pattern from a patterning device onto a substrate using a projection system. The apparatus has a liquid supply system to supply a liquid to a space between the projection system and the substrate. The apparatus also has a fluid removal system including a chamber to hold liquid and having an open end adjacent to a volume in which fluid will be present. The open end removes, through a pressure differential across-the open end when liquid is present in the chamber, substantially only liquid from the volume when liquid in the volume is adjacent to the open end but not gas from the volume when gas in the volume is adjacent to the open end.
    Type: Grant
    Filed: August 5, 2009
    Date of Patent: August 27, 2013
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho
  • Patent number: 8477284
    Abstract: An immersion liquid confinement apparatus confines an immersion liquid in an immersion area that includes a gap between a projection system and an object of exposure in an immersion lithography system. The apparatus also recovers the immersion liquid from the immersion area. The apparatus includes a confinement member and first and second liquid-permeable members. The confinement member includes an outlet and an aperture through which a patterned image is projected onto the object. The first liquid-permeable member covers the outlet and has a first surface that faces the object and a second surface opposite the first surface, the second surface contacting a first chamber. The second liquid-permeable member has first and second oppositely-facing surfaces, the first surface of the second liquid-permeable member contacts the first chamber, the second surface of the second liquid-permeable member contacts a second chamber that is different from the first chamber.
    Type: Grant
    Filed: October 5, 2009
    Date of Patent: July 2, 2013
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Derek Coon
  • Publication number: 20130010271
    Abstract: An immersion lithography apparatus includes a projection system having a final optical element, a movable stage that is movable below the projection system such that a gap exists between the final optical element and a surface of the stage, an immersion liquid being filled in the gap, a liquid confinement member and a liquid diverter. The liquid confinement member maintains the immersion liquid in the gap, and includes a liquid recovery portion that faces the stage surface and recovers liquid from the gap. The liquid recovery portion includes a first porous portion through which a first suction force is applied and a second porous portion through which a second suction force less than the first suction force is applied, the second portion being located outward of the first portion. The liquid diverter is positioned between the stage and at least the first porous portion.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 10, 2013
    Applicant: NIKON CORPORATION
    Inventors: Alex Ka Tim POON, Leonard Wai Fung KHO, Derek COON, Gaurav KESWANI
  • Publication number: 20120262687
    Abstract: Apparatus and methods keep immersion liquid in a space adjacent to an optical assembly. An optical assembly projects an image onto a substrate supported adjacent to the optical assembly by a substrate table. An insertion member insertable into the space between the optical assembly and the substrate, the substrate table, or both, divides the immersion liquid into a first portion and a second portion, the first portion disposed between the optical assembly and the insertion member, and the second portion disposed between the insertion member and the substrate, the substrate table, or both. The insertion member keeps the optical assembly in contact with the first portion when the substrate is moved away from being disposed adjacent to the optical assembly.
    Type: Application
    Filed: June 25, 2012
    Publication date: October 18, 2012
    Applicant: NIKON CORPORATION
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Gaurav Keswani, Derek Coon
  • Patent number: 8289497
    Abstract: An immersion lithography apparatus includes a projection system having a final optical element, a movable stage that is movable below the projection system such that a gap exists between the final optical element and a surface of the stage, an immersion liquid being filled in the gap, a liquid confinement member and a liquid diverter. The liquid confinement member maintains the immersion liquid in the gap, and includes a liquid recovery portion that faces the stage surface and recovers liquid from the gap. The liquid recovery portion includes a first porous portion through which a first suction force is applied and a second porous portion through which a second suction force less than the first suction force is applied, the second portion being located outward of the first portion. The liquid diverter is positioned between the stage and at least the first porous portion.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: October 16, 2012
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Derek Coon, Gaurav Keswani
  • Publication number: 20120257179
    Abstract: Methods and apparatus remove liquid from a surface of a substrate, a substrate table, or both, by applying a vacuum to a passage having first and second opposite ends while the first end is in contact with or close to the liquid. This causes the liquid to flow into the first end of the passage as part of a gas/liquid mixture. At least part of the passage between the first and second ends contacts a porous member. The liquid of the gas/liquid mixture is absorbed into the porous member such that substantially only gas is present at the second end of the passage. Thus, substantially only gas flows towards a vacuum source of the vacuum. A second vacuum may be applied to a collection chamber that contacts the porous member to draw the liquid of the gas/liquid mixture from the passage through the porous member and into the collection chamber.
    Type: Application
    Filed: December 8, 2011
    Publication date: October 11, 2012
    Applicant: NIKON CORPORATION
    Inventors: Derek COON, Leonard Wai Fung KHO, Alex Ka Tim POON
  • Publication number: 20120062866
    Abstract: Electromagnetic actuators are disclosed having at least one actively cooled coil assembly. Exemplary actuators are linear and planar motors of which the cooled coil assembly has a coil having first and second main surfaces. A respective thermally conductive cooling plate is in thermal contact with at least one main surface of the coil. Defined in or on each cooling plate is a coolant passageway that conducts a liquid coolant. A primary pattern of the coolant passageway is coextensive with at least part of the main surface of the coil. The primary pattern can have a secondary pattern through which coolant flows in a manner reducing eddy-current losses. An exemplary secondary pattern is serpentine. An exemplary primary pattern is radial or has a radial aspect, such as an X-shaped pattern. The devices exhibit reduced eddy-current drag.
    Type: Application
    Filed: September 2, 2011
    Publication date: March 15, 2012
    Inventors: Michael B. Binnard, Scott Coakley, Alex Ka Tim Poon, Masahiro Totsu, Derek Coon, Leonard Wai Fung Kho, Gaurav Keswani, Alexander Cooper, Michel Pharand, Matt Bjork
  • Publication number: 20120013861
    Abstract: An apparatus and method provide fluid for immersion lithography. A nozzle member that can move in a direction, is arranged to encircle a space under the optical element. The nozzle member can have an input to supply the immersion liquid to the space under the optical element during the exposure, and an output to remove the immersion liquid from a gap between the nozzle member and the wafer during the exposure. Immersion liquid can be supplied at a first rate to the space from a first portion of the nozzle member and at a second rate to the space from a second portion during the exposure. A wafer substrate is exposed by light through the immersion liquid.
    Type: Application
    Filed: September 22, 2011
    Publication date: January 19, 2012
    Applicant: NIKON CORPORATION
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho
  • Patent number: 8068209
    Abstract: An immersion lithography tool with a diverter element, positioned between the immersion element and the substrate, for altering the “footprint” or shape of the meniscus of the body of immersion liquid between the last optical element and an immersion element on one side, and the substrate on the other side when the substrate is moved. The apparatus includes a substrate holder to hold the substrate having an imaging surface and a projection optical system having a last optical element. The projection optical system projects an image onto a target imaging area on the substrate through the immersion liquid filled in a gap between the imaging surface of the substrate and the last optical element. An immersion element maintains the immersion fluid in the gap. The diverter element is positioned between the immersion element and the substrate.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: November 29, 2011
    Assignee: Nikon Corporation
    Inventors: Alex Ka Tim Poon, Leonard Wai Fung Kho, Guarav Keswani, Derek Coon