Patents by Inventor Kuo-Hsin Li

Kuo-Hsin Li 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: 5877560
    Abstract: A monolithic flip chip microwave integrated circuit module formed using titanium coated copper circuitry and a processing method. A dam is formed on a substrate by forming a thin protective layer such as titanium or other metal on a copper layer formed on a surface of the substrate to which a monolithic microwave integrated circuit is to be attached. The protective layer is oxidized upon exposure to air. Vias or openings are then formed in the oxidized protective layer. Solder is disposed in the openings in the oxidized protective layer, and is confined to the openings while solder is reflowed to attach the integrated circuit to the substrate. The oxidized protective layer serves a dual function that provides both a solder dam and a protective coating for the underlying copper circuitry. Copper surfaces not covered by the oxidized protective layer may be environmentally protected by depositing a thin layer containing electroless plated nickel and electroless plated gold.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: March 2, 1999
    Assignee: Raytheon Company
    Inventors: Cheng P. Wen, Kuo-Hsin Li, Wah S. Wong
  • Patent number: 5602421
    Abstract: A mounting and protective package for a monolithic microwave integrated circuit die (16) operable in the K.sub.a -band is formed of two high temperature co-fired ceramic layers sandwiched by two metal layers (10,12,20,26) that minimize hermetic sealing problems. The package has high frequency input/output lines (40,42), each including a section defining a microstrip line (40a,41a), a section defining a shielded strip line (40b,41b), and a section defining a capacitor (40c, 41c) . The capacitor is precisely defined to provide optimum input/output transmission line impedance that minimizes loss. The integrated circuit die (16) is mounted within a recess (14,46) in the package and is wire bonded (22,24) to input and output capacitors (40c,41c) that in turn are connected with shielded strip lines (40b,41b) and microstrip lines (40a,41a) for both input and output.
    Type: Grant
    Filed: January 31, 1995
    Date of Patent: February 11, 1997
    Assignee: Hughes Aircraft Company
    Inventor: Kuo-Hsin Li