Patents by Inventor Noel C. MacDonald

Noel C. MacDonald 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: 5628917
    Abstract: A masking process resulting from a modified version of the SCREAM process is used for the fabrication of ultra-high aspect ratio, wafer-free, single crystal silicon movable micromechanical devices and frame structures of large vertical depth and narrow linewidth. The process is single-mask, self-aligned and allows the formation of releasable three-dimensional frame-like objects of arbitrary shape which can be made up to about half the wafer thickness in depth and can be subsequently lifted off the substrate and placed on any other material to be used as a mask or to be integrated with other devices. The process consists of a single lithography step and a repeated sequence of thermal oxidations and reactive ion etchings.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: May 13, 1997
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Ali Jazairy
  • Patent number: 5627427
    Abstract: A micrometer scale emitter tip or array is disclosed having precisely located tips and surrounding gates. A silicide on the tips reduces tip work function.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: May 6, 1997
    Assignee: Cornell Research Foundation, Inc.
    Inventors: John H. Das, Noel C. MacDonald, James W. Mayer, James P. Spallas
  • Patent number: 5615143
    Abstract: An ultra-high density optical storage system includes an array of nanometer-scale emitter tips which are associated with corresponding storage surfaces. The tips are optically selectively activated to produce data features simultaneously on their corresponding storage surfaces, with the resulting data features having diameters approximately the same as the diameters of the emitter tips. The array is scannable to selected locations, whereby a data set can be stored in parallel at each location. Because of the small size of the data features, the locations of adjacent features can be spaced apart by a distance on the order of 10 nm for ultradense storage.Stored data can be selectively read out optically by positioning the emitter tip array at the location of the data set to be read and directing light onto the storage surfaces for each tip. Light reflected from the surfaces will correspond to the presence or absence of a data feature at each tip for parallel readout.
    Type: Grant
    Filed: September 19, 1994
    Date of Patent: March 25, 1997
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Yu-hwa Lo
  • Patent number: 5610335
    Abstract: A microelectromechanical accelerometer having submicron features is fabricated from a single crystal silicon substrate. The accelerometer includes a movable portion incorporating an axial beam carrying laterally-extending high aspect ratio released fingers cantilevered above the floor of a cavity formed in the substrate during the fabrication process. The movable portion is supported by restoring springs having controllable flexibility to vary the resonant frequency of the structure. A multiple-beam structure provides stiffness in the movable portion for accuracy.
    Type: Grant
    Filed: May 19, 1994
    Date of Patent: March 11, 1997
    Assignee: Cornell Research Foundation
    Inventors: Kevin A. Shaw, Scott G. Adams, Noel C. MacDonald
  • Patent number: 5563343
    Abstract: A microelectromechanical accelerometer having submicron features is fabricated from a single crystal silicon substrate. The accelerometer includes a movable portion incorporating an axial beam carrying laterally-extending high aspect ratio released fingers cantilevered above the floor of a cavity formed in the substrate during the fabrication process. The movable portion is supported by restoring springs having controllable flexibility to vary the resonant frequency of the structure. A multiple-beam structure provides stiffness in the movable portion for accuracy.
    Type: Grant
    Filed: May 26, 1993
    Date of Patent: October 8, 1996
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Kevin A. Shaw, Scott G. Adams, Noel C. MacDonald
  • Patent number: 5536988
    Abstract: A microelectromechanical compound stage microactuator assembly capable of motion along x, y, and z axes for positioning and scanning integrated electromechanical sensors and actuators is fabricated from submicron suspended single crystal silicon beams. The microactuator incorporates an interconnect system for mechanically supporting a central stage and for providing electrical connections to componants of the microactuator and to devices carried thereby. The microactuator is fabricated using a modified single crystal reactive etching and metallization process which incorporates an isolation process utilizing thermal oxidation of selected regions of the device to provide insulating segments which define conductive paths from external circuitry to the actuator components and to microelectronic devices such as gated field emitters carried by the actuator.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: July 16, 1996
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Z. Lisa Zhang, Noel C. MacDonald
  • Patent number: 5506175
    Abstract: A microelectromechanical compound stage microactuator assembly capable of motion along x, y, and z axes for positioning and scanning integrated electromechanical sensors and actuators is fabricated from submicron suspended single crystal silicon beams. The microactuator incorporates an interconnect system for mechanically supporting a central stage and for providing electrical connections to componants of the microactuator and to devices carried thereby. The microactuator is fabricated using a modified single crystal reactive etching and metallization process which incorporates an isolation process utilizing thermal oxidation of selected regions of the device to provide insulating segments which define conductive paths from external circuitry to the actuator components and to microelectronic devices such as gated field emitters carried by the actuator.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: April 9, 1996
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Z. Lisa Zhang, Noel C. MacDonald
  • Patent number: 5449903
    Abstract: Self-aligned, opposed, nanometer dimension tips are fabricated in pairs, one of each pair being located on a movable, single crystal beam, with the beam being movable in three dimensions with respect to a substrate carrying the other tip of a pair. Motion of one tip with respect to the other is controlled or sensed by transducers formed on the supporting beams. Spring means in each beam allow axial motion of the beam. The tips and beams are fabricated from single crystal silicon substrate, and the tips may be electrically isolated from the substrate by fabricating insulating segments in the beam structure.
    Type: Grant
    Filed: June 15, 1993
    Date of Patent: September 12, 1995
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Susanne C. Arney, Noel C. MacDonald, Jun J. Yao
  • Patent number: 5426070
    Abstract: A method of fabricating released microelectromechanical and microoptomechanical structures having electrically isolating segments from single crystal silicon includes thermal oxidation steps. The structures are defined using a single mask patterning process, and the structure is partially thermally oxidized. This is followed by a second masking step which is used to define segments to be completely thermally oxidized, and a second oxidation step completes the fabrication of the isolating segment. Thereafter the structure is released from the underlying substrate.
    Type: Grant
    Filed: May 26, 1993
    Date of Patent: June 20, 1995
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Kevin A. Shaw, Z. Lisa Zhang, Noel C. MacDonald
  • Patent number: 5399415
    Abstract: A process for fabricating mechanically interconnected, released, electrically isolated metal microstructures, and circuit components and actuators produced by the process. A dielectric stack on a substrate is patterned and etched to produce trenches in which a metal such as tungsten is deposited. The dielectric is removed from selected regions of the metal to expose metal beams, and to form mechanically interconnecting, electrically insulating hinges supporting the beams. The beams and hinges are then released for relative motion. Electrical potentials may be established between adjacent beams to produce controlled motion.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: March 21, 1995
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Liang-Yu Chen, Noel C. MacDonald
  • Patent number: 5397904
    Abstract: A method for isolating transistors and a microstructure for providing isolation for transistors includes a beam located on a substrate. The beam is formed from the same material as the substrate, preferably single crystal silicon, and is released so as to be suspended in the cavity and spaced apart from the substrate. The beam is supported in the cavity by a cantilever structure or by spaced pedestals, or both. One or more transistors are fabricated in the beam, and are thus isolated from the substrate and may be isolated from each other if desired. Contact beams may also be provided to contact the transistor electrodes for interconnection of adjacent transistors or connection of the transistors to electrical circuitry on the substrate. The contact beams also provide mechanical support for the beams.Multiple beams in side-by-side arrays or stacked arrays may be provided.
    Type: Grant
    Filed: July 2, 1992
    Date of Patent: March 14, 1995
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Susanne C. Arney, Noel C. MacDonald, Jun J. Yao
  • Patent number: 5393375
    Abstract: A process for fabricating submicron movable mechanical structures utilizes chemically assisted ion beam etching and reactive ion etching which are independent of crystal orientation. The process provides released mechanical structures which may be of the same material or of different materials than the surrounding substrate, and a nitride coating may be provided on the released structure for optical applications.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: February 28, 1995
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Zhoying L. Zhang, Gyorgy A. Porkolab
  • Patent number: 5375033
    Abstract: Mechanically movable microstructure fabricated from a single crystal such as silicon and actuator structures for providing a high degree of controlled, precision motion of nanometer-scale variable impedances.
    Type: Grant
    Filed: January 6, 1993
    Date of Patent: December 20, 1994
    Assignee: Cornell Research Foundation, Inc.
    Inventor: Noel C. MacDonald
  • Patent number: 5363021
    Abstract: A massively parallel electron beam array for controllably imaging a target includes a multiplicity of emitter cathodes, each incorporating one or more micron-sized emitter tips. Each tip is controlled by a control electrode to produce an electron stream, and its deflection is controlled by a multielement deflection electrode to permit scanning of a corresponding target region.
    Type: Grant
    Filed: July 12, 1993
    Date of Patent: November 8, 1994
    Assignee: Cornell Research Foundation, Inc.
    Inventor: Noel C. MacDonald
  • Patent number: 5316979
    Abstract: A reactive ion etching process is used for the fabrication of submicron, single crystal silicon, movable mechanical structures and capacitive actuators. The reactive ion etching process gives excellent control of lateral dimensions while maintaining a large vertical depth in the formation of high aspect-ratio freely suspended single crystal silicon structures. The silicon etch process is independent of crystal orientation and produces controllable vertical profiles.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: May 31, 1994
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Zuoying L. Zhang
  • Patent number: 5287082
    Abstract: A submicron resistor having negligible parasitic capacitance includes an isolated released beam carried on a single crystal silicon wafer. The resistor is fabricated by defining a resistor region in the substrate, doping the region to produce the desired resistivity, and etching around the region to produce a resistive island. The island is then isolated from the substrate by oxidation, and is released by removing the oxide to produce an isolated, released resistor beam.
    Type: Grant
    Filed: July 2, 1992
    Date of Patent: February 15, 1994
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Susanne C. Arney, Noel C. MacDonald, Jun J. Yao
  • Patent number: 5235187
    Abstract: Self-aligned, opposed, nanometer dimension tips are fabricated in pairs, one of each pair being located on a movable, single crystal beam, with the beam being movable in three dimensions with respect to a substrate carrying the other tip of a pair. Motion of one tip with respect to the other is controlled or sensed by transducers formed on the supporting beams. Spring means in each beam allow axial motion of the beam. The tips and beams are fabricated from single crystal silicon substrate, and the tips may be electrically isolated from the substrate by fabricating insulating segments in the beam structure.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: August 10, 1993
    Assignee: Cornell Research Foundation
    Inventors: Susanne C. Arney, Noel C. MacDonald, Jun J. Yao
  • Patent number: 5199917
    Abstract: Through a silicon fabrication process, an emitter tip array is produced by electron beam or other suitable submicrometer scale lithography for precise location of the emitters. The emitter tips are formed by an oxidation process which ensures accurate and precise formation of tips having uniform radii. The process also utilizes the oxidation step to precisely align gate electrode apertures with respect to corresponding emitter tips so that large arrays can be formed with great accuracy and reliability.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: April 6, 1993
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, James P. Spallas
  • Patent number: 5198390
    Abstract: A reactive ion etching process is used for the fabrication of submicron, single crystal silicon, movable mechanical structures and capacitive actuators. The reactive ion etching process gives excellent control of lateral dimensions while maintaining a large vertical depth in the formation of high aspect-ratio freely suspended single crystal silicon structures. The silicon etch process is independent of crystal orientation and produces controllable vertical profiles.
    Type: Grant
    Filed: January 16, 1992
    Date of Patent: March 30, 1993
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Zuoying L. Zhang
  • Patent number: 5179499
    Abstract: Mechanically movable microstructure fabricated from a single crystal such as silicon and actuator structures for providing a high degree of controlled, precision motion of nanometer-scale.
    Type: Grant
    Filed: April 14, 1992
    Date of Patent: January 12, 1993
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Noel C. MacDonald, Jun J. Yao