Patents by Inventor David C. Sheridan

David C. Sheridan 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: 8872281
    Abstract: A trench contact silicide is formed on an inner wall of a contact trench that reaches to a buried conductive layer in a semiconductor substrate to reduce parasitic resistance of a reachthrough structure. The trench contact silicide is formed at the bottom, on the sidewalls of the trench, and on a portion of the top surface of the semiconductor substrate. The trench is subsequently filled with a middle-of-line (MOL) dielectric. A contact via may be formed on the trench contact silicide. The trench contact silicide may be formed through a single silicidation reaction with a metal layer or through multiple silicidation reactions with multiple metal layers.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: October 28, 2014
    Assignee: International Business Machines Corporation
    Inventors: Douglas D. Coolbaugh, Jeffrey B. Johnson, Peter J. Lindgren, Xuefeng Lie, James S. Nakos, Bradley A. Omer, Robert M. Rassel, David C. Sheridan
  • Publication number: 20140239498
    Abstract: A trench contact silicide is formed on an inner wall of a contact trench that reaches to a buried conductive layer in a semiconductor substrate to reduce parasitic resistance of a reachthrough structure. The trench contact silicide is formed at the bottom, on the sidewalls of the trench, and on a portion of the top surface of the semiconductor substrate. The trench is subsequently filled with a middle-of-line (MOL) dielectric. A contact via may be formed on the trench contact silicide. The trench contact silicide may be formed through a single silicidation reaction with a metal layer or through multiple silicidation reactions with multiple metal layers.
    Type: Application
    Filed: August 9, 2012
    Publication date: August 28, 2014
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Douglas D. Coolbaugh, Jeffrey B. Johnson, Peter J. Lindgren, Xuefeng Liu, James S. Nakos, Bradley A. Orner, Robert M. Rassel, David C. Sheridan
  • Patent number: 8659057
    Abstract: A vertical junction field effect transistor (VJFET) having a self-aligned pin, a p+/n/n+ or a p+/p/n+ gate-source junction is described. The device gate can be self-aligned to within 0.5 ?m to the source in order to maintain good high voltage performance (i.e. low DIBL) while reducing gate-source junction leakage under reverse bias. The device can be a wide-bandgap semiconductor device such as a SiC vertical channel junction field effect. Methods of making the device are also described.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: February 25, 2014
    Assignee: Power Integrations, Inc.
    Inventors: Andrew Ritenour, David C. Sheridan
  • Patent number: 8513675
    Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs). The devices have raised regions with sloped sidewalls which taper inward. The sidewalls can form an angle of 5° or more from vertical to the substrate surface. The devices can have dual-sloped sidewalls in which a lower portion of the sidewalls forms an angle of 5° or more from vertical and an upper portion of the sidewalls forms an angle of <5° from vertical. The devices can be made using normal (i.e., 0°) or near normal incident ion implantation. The devices have relatively uniform sidewall doping and can be made without angled implantation.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: August 20, 2013
    Assignee: Power Integrations, Inc.
    Inventors: David C. Sheridan, Andrew P. Ritenour
  • Patent number: 8507335
    Abstract: Semiconductor devices are described wherein current flow in the device is confined between the rectifying junctions (e.g., p-n junctions or metal-semiconductor junctions). The device provides non-punch-through behavior and enhanced current conduction capability. The devices can be power semiconductor devices as such as Junction Field-Effect Transistors (VJFETs), Static Induction Transistors (SITs), Junction Field Effect Thyristors, or JFET current limiters. The devices can be made in wide bandgap semiconductors such as silicon carbide (SiC). According to some embodiments, the device can be a normally-off SiC vertical junction field effect transistor. Methods of making the devices and circuits comprising the devices are also described.
    Type: Grant
    Filed: May 16, 2011
    Date of Patent: August 13, 2013
    Assignee: Power Integrations, Inc.
    Inventors: Igor Sankin, David C. Sheridan, Joseph Neil Merrett
  • Patent number: 8466017
    Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs) or diodes such as junction barrier Schottky (JBS) diodes or PiN diodes. The devices are made using selective ion implantation using an implantation mask. The devices have implanted sidewalls formed by scattering of normal or near normal incident ions from the implantation mask. Vertical junction field-effect transistors with long channel length are also described. The devices can be made from a wide-bandgap semiconductor material such as silicon carbide (SiC) and can be used in high temperature and high power applications.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: June 18, 2013
    Assignee: Power Integrations, Inc.
    Inventors: David C. Sheridan, Andrew Ritenour
  • Publication number: 20130011979
    Abstract: A vertical junction field effect transistor (VJFET) having a self-aligned pin, a p+/n/n+ or a p+/p/n+ gate-source junction is described. The device gate can be self-aligned to within 0.5 ?m to the source in order to maintain good high voltage performance (i.e. low DIBL) while reducing gate-source junction leakage under reverse bias. The device can be a wide-bandgap semiconductor device such as a SiC vertical channel junction field effect. Methods of making the device are also described.
    Type: Application
    Filed: September 13, 2012
    Publication date: January 10, 2013
    Applicant: SS SC IP, LLC
    Inventors: Andrew RITENOUR, David C. SHERIDAN
  • Patent number: 8338265
    Abstract: A trench contact silicide is formed on an inner wall of a contact trench that reaches to a buried conductive layer in a semiconductor substrate to reduce parasitic resistance of a reachthrough structure. The trench contact silicide is formed at the bottom, on the sidewalls of the trench, and on a portion of the top surface of the semiconductor substrate. The trench is subsequently filled with a middle-of-line (MOL) dielectric. A contact via may be formed on the trench contact silicide. The trench contact silicide may be formed through a single silicidation reaction with a metal layer or through multiple silicidation reactions with multiple metal layers.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: December 25, 2012
    Assignee: International Business Machines Corporation
    Inventors: Douglas D. Coolbaugh, Jeffrey B. Johnson, Peter J. Lindgren, Xuefeng Liu, James S. Nakos, Bradley A. Orner, Robert M. Rassel, David C. Sheridan
  • Patent number: 8288244
    Abstract: A method for forming a lateral passive device including a dual annular electrode is disclosed. The annular electrodes formed from the method include an anode and a cathode. The annular electrodes allow anode and cathode series resistances to be optimized to the lowest values at a fixed device area. In addition, the parasitic capacitance to a bottom plate (substrate) is greatly reduced.
    Type: Grant
    Filed: July 13, 2010
    Date of Patent: October 16, 2012
    Assignee: International Business Machines Corporation
    Inventors: David S. Collins, Jeffrey B. Johnson, Xuefeng Liu, Bradley A. Orner, Robert M. Rassel, David C. Sheridan
  • Publication number: 20120223340
    Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs). The devices have raised regions with sloped sidewalls which taper inward. The sidewalls can form an angle of 5° or more from vertical to the substrate surface. The devices can have dual-sloped sidewalls in which a lower portion of the sidewalls forms an angle of 5° or more from vertical and an upper portion of the sidewalls forms an angle of <5° from vertical. The devices can be made using normal (i.e., 0°) or near normal incident ion implantation. The devices have relatively uniform sidewall doping and can be made without angled implantation.
    Type: Application
    Filed: May 21, 2012
    Publication date: September 6, 2012
    Applicant: SS SC IP, LLC
    Inventors: David C. SHERIDAN, Andrew P. RITENOUR
  • Patent number: 8202772
    Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs). The devices have raised regions with sloped sidewalls which taper inward. The sidewalls can form an angle of 5° or more from vertical to the substrate surface. The devices can have dual-sloped sidewalls in which a lower portion of the sidewalls forms an angle of 5° or more from vertical and an upper portion of the sidewalls forms an angle of <5° from vertical. The devices can be made using normal (i.e., 0°) or near normal incident ion implantation. The devices have relatively uniform sidewall doping and can be made without angled implantation.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: June 19, 2012
    Assignee: SS SC IP, LLC
    Inventors: David C. Sheridan, Andrew P. Ritenour
  • Patent number: 8163612
    Abstract: Methods and heterostructure barrier varactor (HBV) diodes optimized for application with frequency multipliers at providing outputs at submillimeter wave frequencies and above. The HBV diodes include a silicon-containing substrate, an electrode over the silicon-containing substrate, and one or more heterojunction quantum wells of alternating layers of Si and SiGe of one or more electrodes of the diode. Each SiGe quantum well preferably has a floating SiGe layer between adjacent SiGe gradients followed by adjacent Si layers, such that, a single homogeneous structure is provided characterized by having no distinct separations. The plurality of Si/SiGe heterojunction quantum wells may be symmetric or asymmetric.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: April 24, 2012
    Assignee: International Business Machines Corporation
    Inventors: Erik M Dahlstrom, Alvin J Joseph, Robert M Rassel, David C Sheridan
  • Patent number: 8105924
    Abstract: A far subcollector, or a buried doped semiconductor layer located at a depth that exceeds the range of conventional ion implantation, is formed by ion implantation of dopants into a region of an initial semiconductor substrate followed by an epitaxial growth of semiconductor material. A reachthrough region to the far subcollector is formed by outdiffusing a dopant from a doped material layer deposited in the at least one deep trench that adjoins the far subcollector. The reachthrough region may be formed surrounding the at least one deep trench or only on one side of the at least one deep trench. If the inside of the at least one trench is electrically connected to the reachthrough region, a metal contact may be formed on the doped fill material within the at least one trench. If not, a metal contact is formed on a secondary reachthrough region that contacts the reachthrough region.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: January 31, 2012
    Assignee: International Business Machines Corporation
    Inventors: Bradley A. Orner, Robert M. Rassel, David C. Sheridan, Steven H. Voldman
  • Publication number: 20110291107
    Abstract: A vertical junction field effect transistor (VJFET) having a self-aligned pin, a p+/n/n+ or a p+/p/n+ gate-source junction is described. The device gate can be self-aligned to within 0.5 ?m to the source in order to maintain good high voltage performance (i.e. low DIBL) while reducing gate-source junction leakage under reverse bias. The device can be a wide-bandgap semiconductor device such as a SiC vertical channel junction field effect. Methods of making the device are also described.
    Type: Application
    Filed: May 20, 2011
    Publication date: December 1, 2011
    Applicant: SEMISOUTH LABORATORIES, INC.
    Inventors: Andrew Ritenour, David C. Sheridan
  • Patent number: 8058655
    Abstract: Semiconductor devices and methods of making the devices are described. The devices can be junction field-effect transistors (JFETs). The devices have raised regions with sloped sidewalls which taper inward. The sidewalls can form an angle of 5° or more from vertical to the substrate surface. The devices can have dual-sloped sidewalls in which a lower portion of the sidewalls forms an angle of 5° or more from vertical and an upper portion of the sidewalls forms an angle of <5° from vertical. The devices can be made using normal (i.e., 0°) or near normal incident ion implantation. The devices have relatively uniform sidewall doping and can be made without angled implantation.
    Type: Grant
    Filed: November 5, 2009
    Date of Patent: November 15, 2011
    Assignee: SS SC IP, LLC
    Inventors: David C. Sheridan, Andrew P. Ritenour
  • Patent number: 8030167
    Abstract: Methods are disclosed for forming a varied impurity profile for a collector using scattered ions while simultaneously forming a subcollector. In one embodiment, the invention includes: providing a substrate; forming a mask layer on the substrate including a first opening having a first dimension; and substantially simultaneously forming through the first opening a first impurity region at a first depth in the substrate (subcollector) and a second impurity region at a second depth different than the first depth in the substrate. The breakdown voltage of a device can be controlled by the size of the first dimension, i.e., the distance of first opening to an active region of the device. Numerous different sized openings can be used to provide devices with different breakdown voltages using a single mask and single implant. A semiconductor device is also disclosed.
    Type: Grant
    Filed: August 15, 2007
    Date of Patent: October 4, 2011
    Assignee: International Business Machines Corporation
    Inventors: Douglas D. Coolbaugh, Louis D. Lanzerotti, Bradley A. Orner, Jay S. Rascoe, David C. Sheridan, Stephen A. St. Onge
  • Publication number: 20110217829
    Abstract: Semiconductor devices are described wherein current flow in the device is confined between the rectifying junctions (e.g., p-n junctions or metal-semiconductor junctions). The device provides non-punch-through behavior and enhanced current conduction capability. The devices can be power semiconductor devices as such as Junction Field-Effect Transistors (VJFETs), Static Induction Transistors (SITs), Junction Field Effect Thyristors, or JFET current limiters. The devices can be made in wide bandgap semiconductors such as silicon carbide (SiC). According to some embodiments, the device can be a normally-off SiC vertical junction field effect transistor. Methods of making the devices and circuits comprising the devices are also described.
    Type: Application
    Filed: May 16, 2011
    Publication date: September 8, 2011
    Applicant: SEMISOUTH LABORATORIES, INC.
    Inventors: Igor SANKIN, David C. SHERIDAN, Joseph Neil MERRETT
  • Patent number: 8015538
    Abstract: The invention relates to noise isolation in semiconductor devices, and a design structure on which a subject circuit resides. A design structure is embodied in a machine readable medium used in a design process. The design structure includes a deep sub-collector located in a first epitaxial layer, and a doped region located in a second epitaxial layer, which is above the first epitaxial layer. The design structure further includes a reach-through structure penetrating from a surface of the device through the first and second epitaxial layers to the deep sub-collector, and a trench isolation structure penetrating from a surface of the device and surrounding the doped region.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: September 6, 2011
    Assignee: International Business Machines Corporation
    Inventors: Douglas D Coolbaugh, Xuefeng Liu, Robert M. Rassel, David C. Sheridan, Steven H. Voldman
  • Patent number: 7994548
    Abstract: Semiconductor devices are described wherein current flow in the device is confined between the rectifying junctions (e.g., p-n junctions or metal-semiconductor junctions). The device provides non-punch-through behavior and enhanced current conduction capability. The devices can be power semiconductor devices as such as Junction Field-Effect Transistors (VJFETs), Static Induction Transistors (SITs), Junction Field Effect Thyristors, or JFET current limiters. The devices can be made in wide bandgap semiconductors such as silicon carbide (SiC). According to some embodiments, the device can be a normally-off SiC vertical junction field effect transistor. Methods of making the devices and circuits comprising the devices are also described.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: August 9, 2011
    Assignee: Semisouth Laboratories, Inc.
    Inventors: David C. Sheridan, Andrew Ritenour
  • Patent number: 7977713
    Abstract: Semiconductor devices are described wherein current flow in the device is confined between the rectifying junctions (e.g., p-n junctions or metal-semiconductor junctions). The device provides non-punch-through behavior and enhanced current conduction capability. The devices can be power semiconductor devices as such as Junction Field-Effect Transistors (VJFETs), Static Induction Transistors (SITs), Junction Field Effect Thyristors, or JFET current limiters. The devices can be made in wide bandgap semiconductors such as silicon carbide (SiC). According to some embodiments, the device can be a normally-off SiC vertical junction field effect transistor. Methods of making the devices and circuits comprising the devices are also described.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: July 12, 2011
    Assignee: Semisouth Laboratories, Inc.
    Inventors: Igor Sankin, David C. Sheridan, Joseph Neil Merrett