Patents by Inventor Y. S. Edmund Sun

Y. S. Edmund Sun 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).

  • Control of valley current in a unijunction transistor by electron irradiation
    Patent number: 4292644
    Abstract: An improved unijunction transistor having increased valley current is characterized by a region of locally lower lifetime proximate the emitter-base junction. The lifetime is reduced either by overall irradiation of the device or, more preferably, by selective irradiation of the junction area alone.
    Type: Grant
    Filed: April 2, 1979
    Date of Patent: September 29, 1981
    Assignee: General Electric Company
    Inventors: Hing C. Chu, Y. S. Edmund Sun
  • Control of valley current in a unijunction transistor by electron irradiation
    Patent number: 4230791
    Abstract: An improved unijunction transistor having increased valley current is characterized by a region of locally lower lifetime proximate the emitter-base junction. The lifetime is reduced either by overall irradiation of the device or, more preferably, by selective irradiation of the junction area alone.
    Type: Grant
    Filed: April 2, 1979
    Date of Patent: October 28, 1980
    Assignee: General Electric Company
    Inventors: Hing C. Chu, Y. S. Edmund Sun
  • Selective irradiation of thyristors
    Patent number: 4134778
    Abstract: The dv/dt characteristics of a bidirectional thyristor are improved by irradiating selected portions of the device with high energy crystal lattice-damaging particles. In an exemplary embodiment, the commutating dv/dt of a triac is enhanced by the masked, selective irradiation of the boundaries between conducting portions and between the gate and the conducting portions.
    Type: Grant
    Filed: September 2, 1977
    Date of Patent: January 16, 1979
    Assignee: General Electric Company
    Inventors: William W. Sheng, Y. S. Edmund Sun, Edward G. Tefft