Patents Assigned to Redwood Microsystems
  • Patent number: 7047814
    Abstract: A force or pressure transducer is disclosed. In one embodiment, the transducer has a substrate, a dielectric material disposed on the substrate, a spacing member disposed on the dielectric material, and a resilient element disposed on the dielectric material and the spacing member. A portion of the resilient element is separated from the dielectric material, and a portion of the resilient element is in contact with the dielectric material. The contact area between the resilient element and the dielectric material varies in response to movement of the resilient element. Changes in the contact area alter the capacitance of the transducer, which can be measured by circuit means.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: May 23, 2006
    Assignee: Redwood Microsystems, Inc.
    Inventors: Art Zias, Phil Mauger, Sean Cahill, Norm Nystrom, Albert K. Henning
  • Patent number: 6986365
    Abstract: A method for achieving high flow in valves with small actuation distance is described. A detailed description for a silicon microvalve is provided. An algorithm is described for designing optimized valves.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: January 17, 2006
    Assignee: Redwood Microsystems
    Inventors: Albert K. Henning, Michael Selser, Bradford A. Cozad
  • Publication number: 20050211301
    Abstract: Integrated micro-valve is formed to control fluid flow and pressure. The valve converts supplied energy to mechanical energy through an energy conversion means resident above a flexible wall or membrane. In one embodiment a sealed cavity contains a fluid that expands and contracts as it is heated or cooled, thus causing the flexible wall to move. Movement of this wall or membrane is used to move a valve element and dynamically control the opening or closing of a valve port over a predetermined range. Additional stiffening means are added to the membrane to improve performance.
    Type: Application
    Filed: March 26, 2004
    Publication date: September 29, 2005
    Applicant: Redwood MicroSystems, Inc
    Inventors: James Harris, Michael Selser, Bradford Cozad, Albert Henning
  • Patent number: 6907904
    Abstract: A novel fluid delivery system includes a mounting panel, where the mounting panel includes channels that define the flow of fluid between any flow-control components mounted on the mounting panel. The mounting panel comprises a top plate and a bottom plate, and the channels are carved out of the underside of the top plate and are enclosed by the bottom plate. In a complex fluid delivery system having many fluid channels, the mounting panel may include one or more interior panels with additional channels carved out of the interior plates to accommodate all routing paths. The channels run in two or more directions to connect two or more gas/channel sticks together.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: June 21, 2005
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, Selser J. Michael
  • Publication number: 20050067029
    Abstract: A method for achieving high flow in valves with small actuation distance is described. A detailed description for a silicon microvalve is provided. An algorithm is described for designing optimized valves.
    Type: Application
    Filed: September 30, 2003
    Publication date: March 31, 2005
    Applicant: Redwood MicroSystems, Inc.
    Inventors: Albert Henning, Michael Selser, Bradford Cozad
  • Patent number: 6869818
    Abstract: A method for producing a corrosion-resistant channel in a wetted path of a silicon device enables such device to be used with corrosive compounds, such as fluorine. A wetted path of a MEMS device is coated with either (1) an organic compound resistant to attack by atomic fluorine or (2) a material capable of being passivated by atomic fluorine. The device is then exposed to a gas that decomposes into active fluorine compounds when activated by a plasma discharge. One example of such a gas is CF4, an inert gas that is easier and safer to work with than volatile gases like ClF3. The gas will passivate the material (if applicable) and corrode any exposed silicon. The device is tested in such a manner that any unacceptable corrosion of the wetted path will cause the device to fail. If the device operates properly, the wetted path is deemed to be resistant to corrosion by fluorine or other corrosive compounds, as applicable.
    Type: Grant
    Filed: November 18, 2002
    Date of Patent: March 22, 2005
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, Sapna Patel
  • Patent number: 6325886
    Abstract: A method of attaching a micromechanical fluid control device to a substrate includes the steps of forming a first ring of a first adhesive around an aperture defined between a micromechanical fluid control device and a substrate. The first adhesive forms a first interface between the micromechanical fluid control device and the substrate that is clean and corrosion resistant. A second ring of a second adhesive is applied around the first ring. The second adhesive forms a second interface between the micromechanical fluid control device and the substrate that is hermetic.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: December 4, 2001
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, Michael J. Selser, Walter A. Weber
  • Patent number: 6237394
    Abstract: A method of correcting drift in a sensor includes the step of identifying a calibration command. A nominal zero pressure sensor drift correction factor for the sensor is identified by relying upon a calibration voltage value and a calibration temperature value secured at a nominal zero pressure condition. Sensor output is subsequently adjusted according to the nominal zero pressure sensor drift correction factor.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: May 29, 2001
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, Babak Taheri, Errol Arkilic
  • Patent number: 6160243
    Abstract: A micromachined fluid control apparatus includes a micromachined boiler with a thermally conductive housing that has a housing exterior surface and a housing interior surface. The housing interior surface defines an interior void that has a fluid positioned within it. A heat source is incorporated with the housing exterior surface. The heat source selectively generates heat that is conducted through the thermally conductive housing so as to selectively expand the fluid in a predetermined manner. A load resistor may be positioned within the thermally conductive housing. Current may be driven through the load resistor in a predetermined manner to further control the selective expansion of the fluid.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: December 12, 2000
    Assignee: Redwood Microsystems, Inc.
    Inventor: Bradford Allen Cozad
  • Patent number: 6149123
    Abstract: Integrated, electrically operable micro-valves are formed to control fluid flow and pressure. These valves convert electrical energy to mechanical energy through an energy conversion device having a sealed cavity with a flexible wall. The sealed cavity contains a fluid that expands and contracts as it is heated or cooled, thus causing the flexible wall to move. Movement of this wall or membrane is used to move a valve element and dynamically control the opening or closing of a valve port over a predetermined range.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: November 21, 2000
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, Bradford A. Cozad, Dean Allyn Hopkins, Jr., John S. Fitch
  • Patent number: 6129331
    Abstract: A thernopneumatic valve comprises a fluid channel plate defining a fluid port. A diaphragm plate is attached to the fluid channel plate. The diaphragm plate includes a displaceable diaphragm to selectively obstruct the fluid port of the fluid channel plate. A thermal isolating heater is connected to the diaphragm plate. The thermal isolating heater includes a thermal isolating heater body with a heating surface, a perimeter wall defining an extended axial cavity to confine a thermopneumatic working fluid that is used to control the position of the displaceable diaphragm, and a diaphragm obstruction structure to limit the motion of the displaceable diaphragm into the extended axial cavity.
    Type: Grant
    Filed: May 20, 1998
    Date of Patent: October 10, 2000
    Assignee: Redwood Microsystems
    Inventors: Albert Karl Henning, Mark Zdeblick, John Stuart Fitch, Dean Allyn Hopkins, Jr., Leslie Joe Lilly
  • Patent number: 6123107
    Abstract: An apparatus for mounting micromechanical fluid control components includes a manifold interface plate adaptable for connection to a manifold substrate oriented in a horizontal plane. The manifold interface plate receives mounting stress forces from the manifold substrate along the horizontal plane. An orthogonal component plate is connected to the manifold interface plate in a vertical plane with respect to the horizontal plane of the manifold substrate. The orthogonal component plate includes an orthogonal mounting surface with a micromechanical fluid control component mounted on it. The position of the micromechanical fluid control component on the orthogonal mounting surface substantially isolates the micromechanical fluid control component from the mounting stress forces.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: September 26, 2000
    Assignee: Redwood Microsystems, Inc.
    Inventors: Michael J. Selser, Errol B. Arkilic, Babak A. Taheri
  • Patent number: 5865417
    Abstract: A genus of integrated valves having an integrated actuator with a thin, flexible membrane formed of silicon driven by pressure of a fluid trapped in a cavity formed by bonding a first and second die. The cavity has a resistor formed therein through which current is driven to cause the pressure to rise and the flexible membrane to flex. Movement of membrane is used to drive a valve element to a position where it unblocks a port to open the valve. This genus includes species such as ultra clean embodiments where a containment barrier keeps ultra clean processing gases confined to a wetted area having materials and bonding agents selected so as to be chemically compatible with the materials and conditions in the wetted area. Low leak species include a compliant material for a valve seat which is deformed by a ridge surrounding a port in the closed position. It is this port which is blocked and unblocked by movement of the valve element to close and open the valve.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: February 2, 1999
    Assignee: Redwood Microsystems, Inc.
    Inventors: James M. Harris, John S. Fitch, Bradford A. Cozad, Dean Allyn Hopkins, Jr.
  • Patent number: 5270125
    Abstract: A laminated structure includes a wafer member with a membrane attached thereto, the membrane being formed of substantially hydrogen-free boron nitride having a nominal composition B.sub.3 N. The structure may be a component in a mechanical device for effecting a mechanical function, or the membrane may form a masking layer on the wafer. The structure includes a body formed of at least two wafer members laminated together with a cavity formed therebetween, with the boron nitride membrane extending into the cavity so as to provide the structural component such as a support for a heating element or a membrane in a gas valve. In another aspect borom is selectively diffused from the boron nitride into a <100> surface of a silicon wafer. The surface is then exposed to EDP etchant to which the diffusion layer is resistant, thereby forming a channel the wafer member with smooth walls for fluid flow.
    Type: Grant
    Filed: October 25, 1991
    Date of Patent: December 14, 1993
    Assignee: Redwood Microsystems, Inc.
    Inventors: William G. America, Richard R. Poole