Patents by Inventor Olin K. Hartin

Olin K. Hartin 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).

  • Counter-doped varactor structure and method
    Patent number: 7821103
    Abstract: An improved varactor diode (40) is obtained by providing a substrate (41) having a first surface (43), in which are formed a P+ region (53, 46) proximate the first surface (43), a first N region (54, 45) located beneath the P+ region (53, 46), an N well region (56, 44) located beneath the first N region (54, 45) and a first P counter-doped region (55) located between the first N region (54, 45) and the N well region (56, 44), thereby forming an P+NPN structure for the varactor diode. In some embodiments, a second P-type counter-doped region (59) is provided within the N-well region (56, 44) so as to reduce the N doping concentration within the N well region (56, 44) but without creating a further PN junction therein. The net doping profile (52) provides varactor diodes (40) having a larger tuning ratio than varactors (20) without such counter-doped regions. By interchanging N and P regions an N+PNP varactor is obtained.
    Type: Grant
    Filed: September 9, 2008
    Date of Patent: October 26, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Chun-Li Liu, Olin K. Hartin, Jay P. John, Vishal P. Trivedi, James A. Kirchgessner