Patents by Inventor Theresa M. Keller

Theresa M. Keller 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).

  • Patent number: 8546908
    Abstract: A semiconductor amplifier is provided comprising, a substrate and one or more unit amplifying cells (UACs) formed on the substrate, wherein each UAC is laterally surrounded by a first lateral dielectric filled trench (DFT) isolation wall extending at least to the substrate and multiple UACs are surrounded by a second lateral DFT isolation wall of similar depth outside the first isolation walls, and further semiconductor regions lying between the first isolation walls when two or more unit cells are present, and/or lying between the first and second isolation walls, are electrically floating with respect to the substrate. This reduces the parasitic capacitance of the amplifying cells and improves the power added efficiency. Excessive leakage between buried layer contacts when using high resistivity substrates is avoided by providing a further semiconductor layer of intermediate doping between the substrate and the buried layer contacts.
    Type: Grant
    Filed: June 14, 2011
    Date of Patent: October 1, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Dragan Zupac, Brian D. Griesbach, Theresa M. Keller, Joel M. Keys, Sandra J. Wipf, Evan F. Yu
  • Publication number: 20110241159
    Abstract: A semiconductor amplifier is provided comprising, a substrate and one or more unit amplifying cells (UACs) formed on the substrate, wherein each UAC is laterally surrounded by a first lateral dielectric filled trench (DFT) isolation wall extending at least to the substrate and multiple UACs are surrounded by a second lateral DFT isolation wall of similar depth outside the first isolation walls, and further semiconductor regions lying between the first isolation walls when two or more unit cells are present, and/or lying between the first and second isolation walls, are electrically floating with respect to the substrate. This reduces the parasitic capacitance of the amplifying cells and improves the power added efficiency. Excessive leakage between buried layer contacts when using high resistivity substrates is avoided by providing a further semiconductor layer of intermediate doping between the substrate and the buried layer contacts.
    Type: Application
    Filed: June 14, 2011
    Publication date: October 6, 2011
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Dragan Zupac, Brian D. Griesbach, Theresa M. Keller, Joel M. Keys, Sandra J. Wipf, Evan F. Yu
  • Patent number: 7982282
    Abstract: A semiconductor amplifier is provided comprising, a substrate and one or more unit amplifying cells (UACs) formed on the substrate, wherein each UAC is laterally surrounded by a first lateral dielectric filled trench (DFT) isolation wall extending at least to the substrate and multiple UACs are surrounded by a second lateral DFT isolation wall of similar depth outside the first isolation walls, and further semiconductor regions lying between the first isolation walls when two or more unit cells are present, and/or lying between the first and second isolation walls, are electrically floating with respect to the substrate. This reduces the parasitic capacitance of the amplifying cells and improves the power added efficiency. Excessive leakage between buried layer contacts when using high resistivity substrates is avoided by providing a further semiconductor layer of intermediate doping between the substrate and the buried layer contacts.
    Type: Grant
    Filed: April 25, 2008
    Date of Patent: July 19, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Dragan Zupac, Brian D. Griesbach, Theresa M. Keller, Joel M. Keys, Sandra J. Wipf, Evan F. Yu
  • Patent number: 7821102
    Abstract: A power transistor (210) comprises a plurality of unit cell devices (212), a base contact configuration, an emitter contact configuration, and a collector contact configuration. The plurality of unit cell devices is arranged along an axis (194), each unit cell device including base (80), emitter (82), and collector (84) portions. The base contact configuration includes (i) a first base feed (150) coupled to the base portion of each unit cell device via a first end of at least one base finger (154) associated with a corresponding unit cell device and (ii) a second base feed (152) coupled to the base portion of each unit cell device via an opposite end of the at least one base finger associated with the corresponding unit cell device.
    Type: Grant
    Filed: February 5, 2007
    Date of Patent: October 26, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Dragan Zupac, Sandra J. Wipf, Theresa M. Keller, Elizabeth C. Glass
  • Publication number: 20090267689
    Abstract: A semiconductor amplifier is provided comprising, a substrate and one or more unit amplifying cells (UACs) formed on the substrate, wherein each UAC is laterally surrounded by a first lateral dielectric filled trench (DFT) isolation wall extending at least to the substrate and multiple UACs are surrounded by a second lateral DFT isolation wall of similar depth outside the first isolation walls, and further semiconductor regions lying between the first isolation walls when two or more unit cells are present, and/or lying between the first and second isolation walls, are electrically floating with respect to the substrate. This reduces the parasitic capacitance of the amplifying cells and improves the power added efficiency. Excessive leakage between buried layer contacts when using high resistivity substrates is avoided by providing a further semiconductor layer of intermediate doping between the substrate and the buried layer contacts.
    Type: Application
    Filed: April 25, 2008
    Publication date: October 29, 2009
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventors: Dragan Zupac, Brian D. Griesbach, Theresa M. Keller, Joel E. Keys, Sandra J. Wipf, Evan F. Yu
  • Publication number: 20080150082
    Abstract: A power transistor (210) comprises a plurality of unit cell devices (212), a base contact configuration, an emitter contact configuration, and a collector contact configuration. The plurality of unit cell devices is arranged along an axis (194), each unit cell device including base (80), emitter (82), and collector (84) portions. The base contact configuration includes (i) a first base feed (150) coupled to the base portion of each unit cell device via a first end of at least one base finger (154) associated with a corresponding unit cell device and (ii) a second base feed (152) coupled to the base portion of each unit cell device via an opposite end of the at least one base finger associated with the corresponding unit cell device.
    Type: Application
    Filed: February 5, 2007
    Publication date: June 26, 2008
    Inventors: Dragan Zupac, Sandra J. Wipf, Theresa M. Keller, Elizabeth C. Glass
  • Patent number: 5837590
    Abstract: A vertical PNP transistor and method for making it provide a transistor in a surface layer (12), which may be an epitaxial layer, of P- type conductivity at a surface of a substrate (11) of P+ type conductivity. An isolation region (14) of N- type conductivity in the P- surface layer (12) contains a collector region (25) of P- type conductivity. A base region (30) of N type conductivity is contained in the collector region (25), and an emitter region (40) of P+ type conductivity is contained in the base region (30). The base region (30) may be provided with a higher N type impurity concentration than a P type impurity concentration of the collector region (25). At least the collector region (25) and the base region (30) may be self aligned. The collector region (25) may be of thickness of about 2.2 .mu.m, the base region (30) of thickness of about 0.1 .mu.m, and the emitter region (40) of thickness of about 0.4 .mu.m.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: November 17, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Lawrence F. Latham, Theresa M. Keller