Patents by Inventor Chi K. Kwok

Chi K. Kwok 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).

  • Method of forming multilayered electrodes for ferroelectric devices consisting of conductive layers and interlayers formed by chemical reaction
    Patent number: 5491102
    Abstract: A ferroelectric device is constructed using a bottom electrode composed of a conducting oxide such as RuO.sub.x, on a substrate such as silicon or silicon dioxide. A ferroelectric material such as lead zirconate titanate (PZT) is deposited on the bottom electrode, and a conducting interlayer is formed at the interface between the ferroelectric and the electrode. This interlayer is created by reaction between the materials of the ferroelectric and electrode, and in this case would be Pb.sub.2 Ru.sub.2 O.sub.7-x. A conductive top layer is deposited over the ferroelectric. This top layer may be a metal, or it may be the same type of materials as the bottom electrode, in which case another interlayer can be formed at the interface. A device constructed in this manner has the property of lower degradation due to fatigue, breakdown, and aging.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: February 13, 1996
    Assignees: Ceram Incorporated, Sharp Kabushiki Kaisha, Virginia Polytechnic Institute and State University
    Inventors: Seshu B. Desu, In K. Yoo, Chi K. Kwok, Dilip P. Vijay