Patents by Inventor Silai V. Krishnaswamy

Silai V. Krishnaswamy 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: 10224413
    Abstract: A radio-frequency (RF) carbon-nanotube (CNT) field effect transistor (FET) device. The device includes a source contact, a drain contact, semi-conducting CNTs positioned between the source and drain contacts, high-? gate dielectric, and a local backgate positioned below the semi-conducting CNTs, in which the local backgate is capable of RF performance and is capable of being used in a backgate burnout process used to enhance the semiconducting to metallic tube ratio of the device.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: March 5, 2019
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Joseph A. Payne, Wayne S. Miller, Monica P. Lilly, Silai V. Krishnaswamy
  • Patent number: 9154107
    Abstract: A bulk acoustic resonator assembly and methods for fabricated the resonator assembly is provided. The resonator includes a cavity on a first surface of a substrate, with a sheet of low acoustic loss material suspended over the cavity. The sheet of low acoustic loss material is configured such that an associated fundamental frequency of the sheet of low acoustic loss material is a function of a length of the sheet of low acoustic loss material in a direction parallel to the first surface of the substrate. A transducer includes an electromechanical layer on the sheet of low acoustic loss material and a patterned conductive material formed on the electromechanical material. The transducer is configured to induce vibrations in the low acoustic loss material upon application of an electrical signal to the conductive pattern.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: October 6, 2015
    Assignees: Northrop Grumman Systems Corporation, The Trustees of the University of Pennsylvania
    Inventors: John D. Adam, Silai V. Krishnaswamy, Gianluca Piazza
  • Publication number: 20120081195
    Abstract: A bulk acoustic resonator assembly and methods for fabricated the resonator assembly is provided. The resonator includes a cavity on a first surface of a substrate, with a sheet of low acoustic loss material suspended over the cavity. The sheet of low acoustic loss material is configured such that an associated fundamental frequency of the sheet of low acoustic loss material is a function of a length of the sheet of low acoustic loss material in a direction parallel to the first surface of the substrate. A transducer includes an electromechanical layer on the sheet of low acoustic loss material and a patterned conductive material formed on the electromechanical material. The transducer is configured to induce vibrations in the low acoustic loss material upon application of an electrical signal to the conductive pattern.
    Type: Application
    Filed: May 28, 2010
    Publication date: April 5, 2012
    Inventors: John D. Adam, Silai V. Krishnaswamy, Gianluca Piazza
  • Patent number: 7989249
    Abstract: A method of manufacturing a micro-electrical-mechanical system with thermally isolated active elements. Such a system may embody a bolometer, which is well suited for detecting electromagnetic radiation between 90 GHz and 30 THz while operating at room temperature. The method also discloses a generalized process for manufacturing circuitry incorporating active and passive micro-electrical-mechanical systems in a silicon wafer.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: August 2, 2011
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Nathan Bluzer, Silai V. Krishnaswamy, Philip C. Smith
  • Patent number: 7786653
    Abstract: The present invention provides a MEMS piezoelectric switch that has an articulated unimorph bridge attached to a substrate. The bridge includes a passive layer of zirconia and at least one silicon-based material, an active layer of a piezoelectric material that has a high piezoelectric coefficient, at least one pair of interdigitated electrodes, disposed on the top surface of the active layer and across which the bias voltage is applied, and a top contact electrode. A bottom contact electrode is provided on the substrate, and signals flow through the switch when the top and bottom contact electrodes contact one another.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: August 31, 2010
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Carl B. Freidhoff, Silai V. Krishnaswamy
  • Publication number: 20100197063
    Abstract: A method of manufacturing a micro-electrical-mechanical system with thermally isolated active elements. Such a system may embody a bolometer, which is well suited for detecting electromagnetic radiation between 90 GHz and 30 THz while operating at room temperature. The method also discloses a generalized process for manufacturing circuitry incorporating active and passive micro-electrical-mechanical systems in a silicon wafer.
    Type: Application
    Filed: February 4, 2009
    Publication date: August 5, 2010
    Applicant: Northrop Grumman Systems Corporation
    Inventors: Nathan BLUZER, Silai V. KRISHNASWAMY, Philip C. SMITH
  • Patent number: 7561760
    Abstract: An apparatus and a method for steering optical frequency beams using nanowire. A method includes providing one or more nanowire waveguide arrays, generating an optical frequency beam, wherein the optical frequency beam is incident on the one or more nanowire waveguide arrays, controlling the one or more nanowire waveguide arrays to produce a phase delay in the optical frequency beam as it traverses the nanowire waveguide array, wherein the phase delay causes the optical frequency beam to deflect upon exiting the one or more nanowire waveguide arrays, and steering the optical frequency beam exiting the one or more nanowire waveguide arrays by increasing or decreasing the phase delay, wherein the angle of deflection of the exiting optical frequency beam is determined by the amount of phase delay.
    Type: Grant
    Filed: July 19, 2006
    Date of Patent: July 14, 2009
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Aaron Anthony Pesetski, Silai V. Krishnaswamy
  • Publication number: 20090081828
    Abstract: The present invention provides methods for singulating microelectromechanical systems (MEMS) die from a wafer. A plurality of MEMS devices are formed on the top surface of a wafer, and a plurality of intersecting scribe lanes are then formed, on the bottom surface of the wafer, to define a plurality of dies, each including at least one MEMS device. The intersecting scribe lanes penetrate the wafer to a depth of about 80%, and the wafer is cleaved along the scribe lanes to separate each of the plurality of dies from the wafer.
    Type: Application
    Filed: September 26, 2007
    Publication date: March 26, 2009
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Carl B. Freidhoff, Silai V. Krishnaswamy, William K. Sterrett
  • Publication number: 20090009030
    Abstract: The present invention provides a MEMS piezoelectric switch that has an articulated unimorph bridge attached to a substrate. The bridge includes a passive layer of zirconia and at least one silicon-based material, an active layer of a piezoelectric material that has a high piezoelectric coefficient, at least one pair of interdigitated electrodes, disposed on the top surface of the active layer and across which the bias voltage is applied, and a top contact electrode. A bottom contact electrode is provided on the substrate, and signals flow through the switch when the top and bottom contact electrodes contact one another.
    Type: Application
    Filed: July 3, 2007
    Publication date: January 8, 2009
    Applicant: NORTHROP GRUMMAN SYSTEMS CORPORATION
    Inventors: Carl B. Freidhoff, Silai V. Krishnaswamy
  • Patent number: 7378782
    Abstract: The disclosed invention relates to achieving micromachined piezoelectrically-actuated diaphragms. The piezoelectric diaphragm includes a central, inactive electrode free region and an annular shaped interdigitated electrode adjacent to the outer periphery of the central region. The diaphragm also may have an inactive annular, electrode free region and an active central, interdigitated electrode region. The diaphragms may be used in, such as, miniature pumps. The pumps may include a plurality of chambers to generate peristaltic pumping of fluids.
    Type: Grant
    Filed: November 26, 2004
    Date of Patent: May 27, 2008
    Assignees: The Penn State Research Foundation, Northrup Grumman Corp.
    Inventors: Susan Trolier McKinstry, Euniki Hong, Carl Baldwin Freidhoff, Silai V Krishnaswamy
  • Patent number: 7253083
    Abstract: First and second semiconductor wafers are bonded together, with at least one of the wafers having a first layer of silicon, an intermediate oxide layer and a second layer of silicon. The first silicon layer is initially mechanically reduced by around 80% to 90% of its thickness. The remaining silicon layer is further reduced by a plasma etch which may leave an uneven thickness. With appropriate masking the uneven thickness is made even by a second plasma etch. Remaining silicon is removed by a dry etch with XeF2 or BrF3 to expose the intermediate oxide layer. Prior to bonding, the semiconductor wafers may be provided with various semiconductor devices to which electrical connections are made through conducting vias formed through the exposed intermediate oxide layer.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: August 7, 2007
    Assignee: Northrop Grumman Corporation
    Inventors: Rowland C. Clarke, Erica C. Elvey, Silai V. Krishnaswamy, Jeffrey D. Hartman