Patents by Inventor Martin C. Wilson

Martin C. Wilson 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).

  • Semiconductor device
    Patent number: 6436780
    Abstract: A number of npn and pnp bipolar transistors are formed in a single chip of silicon, so that some of the transistors have a greater frequency response than others The higher frequency transistors have their emitters located closer to the collectors, by positioning a collector, or emitter, of a transistor in a recessed portion of the surface of the chip. The recess is formed in an accurate and controlled manner by locally oxidising the silicon surface, and subsequently removing the oxide to leave the recess.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: August 20, 2002
    Assignee: Mitel Semiconductor Limited
    Inventors: Peter H Osborne, Martin C Wilson
  • Semiconductor device
    Patent number: 6222249
    Abstract: A number of npn and pnp bipolar transistors is formed in a single chip of silicon, so that some of the transistors have a greater frequency response than others. The higher frequency transistors have their emitters located closer to the collectors, by positioning a collector, or emitter, of a transistor in a recessed portion of the surface of the chip. The recess is formed in an accurate and controlled manner by locally oxidizing the silicon surface, and subsequently removing the oxide to leave the recess.
    Type: Grant
    Filed: June 24, 1999
    Date of Patent: April 24, 2001
    Assignee: Mitel Semiconductor Limited
    Inventors: Peter H Osborne, Martin C. Wilson