Patents by Inventor Weijun Liu

Weijun Liu 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: 20100109195
    Abstract: Release agents with increased affinity toward nano-imprint lithography template surfaces interact strongly with the template during separation of the template from the solidified resist in a nano-imprint lithography process. The strong interaction between the surfactant and the template surface reduces the amount of surfactant pulled off the template surface during separation of a patterned layer from the template in an imprint lithography cycle. Maintaining more surfactant associated with the surface of the template after the separation of the patterned layer from the template may reduce the amount of surfactant needed in a liquid resist to achieve suitable release of the solidified resist from the template during an imprint lithography process. Strong association of the release agent with the surface of the template facilitates the formation of ultra-thin residual layers and dense fine features in nano-imprint lithography.
    Type: Application
    Filed: November 4, 2009
    Publication date: May 6, 2010
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Frank Y. Xu, Weijun Liu
  • Publication number: 20100104852
    Abstract: An imprint lithography template includes a porous material defining a multiplicity of pores with an average pore size of at least about 0.4 nm. The porous material includes silicon and oxygen, and a ratio of Young's modulus (E) to relative density of the porous material with respect to fused silica (pporous/pfused silica) is at least about 10:1. A refractive index of the porous material is between about 1.4 and 1.5. The porous material may form an intermediate layer or a cap layer of an imprint lithography template. The template may include a pore seal layer between a porous layer and a cap layer, or a pore seal layer on top of a cap layer.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 29, 2010
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Edward B. Fletcher, Frank Y. Xu, Weijun Liu, Fen Wan, Marlon Menezes, Kosta S. Selinidis
  • Publication number: 20100098940
    Abstract: A nano-imprint lithography stack includes a nano-imprint lithography substrate, a non-silicon-containing layer solidified from a first polymerizable, non-silicon-containing composition, and a silicon-containing layer solidified from a polymerizable silicon-containing composition adhered to a surface of the non-silicon-containing layer. The non-silicon-containing layer is adhered directly or through one or more intervening layers to the nano-imprint lithography substrate. The silicon-containing layer includes a silsesquioxane with a general formula (R?(4-2z)SiOz)x(HOSiO1.5)y, wherein R? is a hydrocarbon group or two or more different hydrocarbon groups other than methyl, 1<z<2, and x and y are integers.
    Type: Application
    Filed: October 19, 2009
    Publication date: April 22, 2010
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Weijun Liu, Frank Y. Xu
  • Publication number: 20100084376
    Abstract: Porous nano-imprint lithography templates may include pores, channels, or porous layers arranged to allow evacuation of gas trapped between a nano-imprint lithography template and substrate. The pores or channels may be formed by etch or other processes. Gaskets may be formed on an nano-imprint lithography template to restrict flow of polymerizable material during nano-imprint lithography processes.
    Type: Application
    Filed: October 2, 2009
    Publication date: April 8, 2010
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Niyaz Khusnatdinov, Weijun Liu, Frank Y. Xu, Fen Wan, Edward Brian Fletcher, Marlon Menezes
  • Publication number: 20100072671
    Abstract: A nano-imprint lithography template includes a rigid support layer, a cap layer, and a flexible cushion layer positioned between the support layer and the cap layer. Treating an imprint lithography template includes heating the template to desorb gases from the template. Heating the template includes radiating the template at a selected wavelength with, for example, infrared radiation. The selected wavelength may correspond to a wavelength at which the template material is strongly absorbing.
    Type: Application
    Filed: September 25, 2009
    Publication date: March 25, 2010
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Gerard M. Schmid, Weijun Liu, Edward Brian Fletcher, Frank Y. Xu, Fen Wan
  • Publication number: 20090197057
    Abstract: A nano-imprint lithography process includes forming a multiplicity of hydroxyl groups on a surface of a substantially inorganic nano-imprint lithography template, heating the template, and reacting a pre-selected percentage of the hydroxyl groups on the surface of the template with a mono-functional, non-fluorinated compound to form a monolayer coating on the surface of the nano-imprint lithography template. The coated template may be contacted with a polymerizable composition disposed on a nano-imprint lithography substrate, and the polymerizable composition solidified to form a patterned layer. The coated template is separated from the patterned layer.
    Type: Application
    Filed: February 3, 2009
    Publication date: August 6, 2009
    Applicant: Molecular Imprints, Inc.
    Inventors: Frank Y. Xu, Weijun Liu
  • Publication number: 20090140458
    Abstract: An imprint lithography template or imprinting stack includes a porous material defining a multiplicity of pores with an average pore size of at least about 0.4 nm. A porosity of the porous material is at least about 10%. The porous template, the porous imprinting stack, or both may be used in an imprint lithography process to facilitate diffusion of gas trapped between the template and the imprinting stack into the template, the imprinting stack or both, such that polymerizable material between the imprinting stack and the template rapidly forms a substantially continuous layer between the imprinting stack and the template.
    Type: Application
    Filed: November 21, 2008
    Publication date: June 4, 2009
    Applicant: MOLECULAR IMPRINTS, INC.
    Inventors: Frank Y. Xu, Weijun Liu, Edward Brian Fletcher, Sidlgata V. Sreenivasan, Byung Jin Choi, Niyaz Khusnatdinov, Anshuman Cherala, Kosta S. Selinidis
  • Publication number: 20090053535
    Abstract: A multi-layer stack for imprint lithography is formed by applying a first polymerizable composition to a substrate, polymerizing the first polymerizable composition to form a first polymerized layer, applying a second polymerizable composition to the first polymerized layer, and polymerizing the second polymerizable composition to form a second polymerized layer on the first polymerized layer. The first polymerizable composition includes a polymerizable component with a glass transition temperature less than about 25° C., and the first polymerized layer is substantially impermeable to the second polymerizable composition.
    Type: Application
    Filed: August 22, 2008
    Publication date: February 26, 2009
    Applicant: Molecular Imprints, Inc.
    Inventors: Frank Y. Xu, Weijun Liu, Cynthia B. Brooks, Dwayne L. LaBrake, David J. Lentz
  • Publication number: 20080308971
    Abstract: A solid layer is formed by applying a multiplicity of discrete portions of a fluid composition onto a surface of an imprint lithography substrate, and allowing the discrete portions of the composition to spontaneously spread on the surface of the substrate to form a substantially continuous layer. The composition includes a solvent and a solid or a solvent and a polymerizable material. The composition can be a solution or a dispersion. At least some of the solvent is evaporated from the composition, and a solid layer is formed (e.g., polymerized or dried) on the substrate. The solid layer is substantially free of interstitial voids.
    Type: Application
    Filed: June 16, 2008
    Publication date: December 18, 2008
    Applicant: Molecular Imprints, Inc.
    Inventors: Weijun Liu, Frank Y. Xu, Edward Brian Fletcher
  • Patent number: 7060768
    Abstract: Certain complexes containing ligands having a phosphino group, amino group or an imino group, and a second functional group such as amide, ester or ketone, when complexed to transition metals, catalyze the (co)polymerization of olefinic compounds such as ethylene, ?-olefins and/or acrylates. A newly recognized class of ligands for making copolymer containing polar monomers using late transition metal complexes is described.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: June 13, 2006
    Assignees: E.I. duPont de Nemours and Company, University of North Carolina at Chapel Hill
    Inventors: Maurice S. Brookhart, Keith Kunitsky, Weijun Liu, Jon M. Malinoski, Lin Wang, Ying Wang, Lynda Kaye Johnson, Kristina A. Kreutzer, Steven Dale Ittel
  • Publication number: 20040158012
    Abstract: Certain complexes containing ligands having a phosphino group, amino group or an imino group, and a second functional group such as amide, ester or ketone, when complexed to transition metals, catalyze the (co)polymerization of olefinic compounds such as ethylene, &agr;-olefins and/or acrylates. A newly recognized class of ligands for making copolymer containing polar monomers using late transition metal complexes is described.
    Type: Application
    Filed: January 20, 2004
    Publication date: August 12, 2004
    Inventors: Maurice S. Brookhart, Keith Kunitsky, Weijun Liu, Jon M. Malinoski, Lin Wang, Ying Wang, Lynda Kaye Johnson, Kristina A. Kreutzer, Steven Dale Ittel
  • Patent number: 6710007
    Abstract: Certain complexes containing ligands having a phosphino group, amino group or an imino group, and a second functional group such as amide, ester or ketone, when complexed to transition metals, catalyze the (co)polymerization of olefinic compounds such as ethylene, &agr;-olefins and/or acrylates. A newly recognized class of ligands for making copolymer containing polar monomers using late transition metal complexes is described.
    Type: Grant
    Filed: January 25, 2002
    Date of Patent: March 23, 2004
    Assignees: E. I. du Pont de Nemours and Company, University of North Carolina at Chapel Hill
    Inventors: Maurice S. Brookhart, Keith Kunitsky, Weijun Liu, Jon M. Malinoski, Lin Wang, Ying Wang, Lynda Kaye Johnson, Kristina A. Kreutzer, Steven Dale Ittel
  • Publication number: 20030125485
    Abstract: Certain complexes containing ligands having a phosphino group, amino group or an imino group, and a second functional group such as amide, ester or ketone, when complexed to transition metals, catalyze the (co)polymerization of olefinic compounds such as ethylene, &agr;-olefins and/or acrylates. A newly recognized class of ligands for making copolymer containing polar monomers using late transition metal complexes is described.
    Type: Application
    Filed: January 25, 2002
    Publication date: July 3, 2003
    Inventors: Maurice S. Brookhart, Keith Kunitsky, Weijun Liu, Jon M. Malinoski, Lin Wang, Ying Wang, Lynda Kaye Johnson, Kristina A. Kreutzer, Steven Dale Ittel