Patents by Inventor QIANG CUI

QIANG CUI 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).

  • Patent number: 6540866
    Abstract: The present invention is directed to a method for the lamination of fluoropolymers to the surfaces of metals, and especially to copper, gold, and platinum, and to printed circuit board (PCB) substrate at temperatures substantially below the sintering temperatures or melting temperatures of the fluoropolymers. More specifically, the invention is directed to a method for surface modification of fluoropolymers by thermal graft copolymerization with concurrent lamination of metals in the presence of a functional monomer and an adhesive such as an epoxy resin. The process can be carried out under atmospheric conditions and in the complete absence of an added polymerization initiator. The laminated fluoropolymer-metal or fluoropolymer-PCB substrate interfaces exhibit T-peel strengths of no less than 8 N/cm. This invention can also be applied to substantially improve the adhesion between PCB substrates and metals.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: April 1, 2003
    Assignees: Institute of Microelectronics, National University of Singapore
    Inventors: Junfeng Zhang, Cheng Qiang Cui, Thiam Beng Lim, En-Tang Kang
  • Patent number: 6537411
    Abstract: The present invention is directed to a method for the lamination of metals, and especially copper, to the surface of polyimides and derivatives of polyimides at temperatures substantially below the curing temperature of the imide polymers. More specifically, the invention is directed to a method for surface modification of polyimides and derivatives of polyimides by thermal graft copolymerization and interfacial polymerization with concurrent lamination of the metal of interest in the presence of an appropriate functional monomer. The process can be carried out under atmospheric conditions and either in the presence or the complete absence of an added polymerization initiator. The so laminated polyimide-metal interfaces exhibit T-peel adhesion strengths in excess of 16 N/cm. The adhesion strength also exceeds the fracture strength of polyimide films with a thickness of 75 &mgr;m.
    Type: Grant
    Filed: June 28, 2000
    Date of Patent: March 25, 2003
    Assignees: The National University of Singapore, Institute of Microelectronics
    Inventors: En-Tang Kang, Arthur Khoon Siah Ang, Koon Gee Neoh, Cheng Qiang Cui, Thiam Beng Lim
  • Patent number: 6334926
    Abstract: The present invention is directed to a method for the lamination of metals, and especially copper, to the surfaces of fluoropolymers at temperatures substantially below the sintering temperatures or melting temperatures of the fluoropolymers. More specifically, the invention is directed to a method for surface modification of fluoropolymers by thermal graft copolymerization with concurrent lamination of a metal (e.g. copper) in the presence of a functional monomer. The process can be carried out under atmospheric conditions and in the complete absence of an added polymerization initiator. The so-laminated fluoropolymer-metal interfaces exhibit T-peel strengths of no less than 8 N/cm and delaminate via cohesive failure inside the fluoropolymer.
    Type: Grant
    Filed: June 8, 1999
    Date of Patent: January 1, 2002
    Assignee: National University of Singapore and Institute of Microelectronics
    Inventors: En Tang Kang, Jian-Li Shi, Koon Gee Neoh, Kuang Lee Tan, Cheng Qiang Cui, Thiam Beng Lim
  • Patent number: 6274650
    Abstract: Disclosed are liquid epoxy encapsulants comprising a basic bisphenol-type epoxy resin with epoxy groups at each end having an epoxy equivalent of 170-300, and an amine curing agent such as 4,4′-Methylene dianiline with the content of 15-30 wt % with respect to epoxy resins and other additives such as coloring agents, flame retardants, and catalysts. Alphatic and cycloaliphatic epoxy resins and polyamide curing agents can optionally be added to mix with the bisphenol epoxy resin to modify the properties of the liquid epoxy encapsulants, i.e., to decrease their viscosities and to increase their toughness. The liquid epoxy encapsulants of this invention have characteristics of suitable viscosity, fast curing, high adhesion to polyimides and high reliability in the application of flip-chip-on-board (FCOB) encapsulation as underfill materials.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: August 14, 2001
    Assignee: Institute of Microelectronics
    Inventor: Cheng Qiang Cui