Patents by Inventor Yeong-Chang Choug

Yeong-Chang Choug 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).

  • High electron mobility transistor (HEMT) structure with refractory gate metal
    Patent number: 7411226
    Abstract: An InP high electron mobility transistor (HEMT) structure in which a gate metal stack includes an additional thin layer of a refractory metal, such as molybdenum (Mo) or platinum (Pt) at a junction between the gate metal stack and a Schottky barrier layer in the HEMT structure. The refractory metal layer reduces or eliminates long-term degradation of the Schottky junction between the gate metal and the barrier layer, thereby dramatically improving long-term reliability of InP HEMTs, but without sacrifice in HEMT performance, whether used as a discrete device or in an integrated circuit.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: August 12, 2008
    Assignee: Northrop Grumman Corporation
    Inventors: Yeong-Chang Choug, Ronald Grundbacher, Po-Hsin Liu, Denise L. Leung, Richard Lai
  • High electron mobility transistor (HEMT) structure with refractory gate metal
    Publication number: 20060244009
    Abstract: An InP high electron mobility transistor (HEMT) structure in which a gate metal stack includes an additional thin layer of a refractory metal, such as molybdenum (Mo) or platinum (Pt) at a junction between the gate metal stack and a Schottky barrier layer in the HEMT structure. The refractory metal layer reduces or eliminates long-term degradation of the Schottky junction between the gate metal and the barrier layer, thereby dramatically improving long-term reliability of InP HEMTs, but without sacrifice in HEMT performance, whether used as a discrete device or in an integrated circuit.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 2, 2006
    Inventors: Yeong-Chang Choug, Ronald Grundbacher, Po-Hsin Liu, Denise Leung, Richard Lai