Mcnc

Mcnc Research & Development Institute

Research Triangle Institute

Scott Halden Goodwin-Johansson

Brian Rhys Stoner

David Dausch

Sonia Grego

Stephen M Bobbio

Gary Elder McGuire

Farid M Tranjan

Thomas D DuBois

Brian H Augustine

John South Lewis, Lll

James D Jacobson

Youssef Bousaba

Kerstin McKay

Lindsey N Yadon

John South Lewis, Iii

A simplified MEMS optical display device driven by electrostatic forces and associated arrays are provided for. The optical display device includes an optically transparent substrate, an optically transparent fixed electrode disposed on the substrate and a pigmented translucent film disposed on the substrate. A moveable optical shutter is affixed to the substrate and is generally aligned with the fixed electrode and the pigmented translucent film. The moveable optical shutter comprises an electrode element and a biasing element. In addition, a fixed portion attached to the substrate and a distal portion adjacent to the fixed portion defines the optical shutter. When an electrostatic voltage differential is established between the fixed electrode and the optical shutter electrode element the distal portion of the optical shutter will move to controllably regulate the pigmentation of an optical signal.

Mems electrostatically actuated optical display device and associated arrays

A three dimensional photonic crystal and layer-by-layer processes of fabricating the photonic crystal. A substrate is exposed to a plurality of first microspheres made of a first material, the first material being of a type that will bond to the templated substrate and form a self-passivated layer of first microspheres to produce a first layer. The first layer is exposed to a plurality of second microspheres made of a second material, the second material being of a type that will bond to the first layer and form a self-passivated layer of second microspheres. This layering of alternating first and second microspheres can be repeated as desired to build a three dimensional photonic crystal of desired geometry. Charged polymers such as polyelectrolyte coatings can be used to create the bonds.

Layered photonic crystals

A three dimensional photonic crystal and layer-by-layer processes of fabricating the photonic crystal. A templated substrate is exposed to a plurality of first microspheres made of a first material, the first material being of a type that will bond to the templated substrate and form a self-passivated layer of first microspheres to produce a first layer. The first layer is exposed to a plurality of second microspheres made of a second material, the second material being of a type that will bond to the first layer and form a self-passivated layer of second microspheres. This layering of alternating first and second microspheres can be repeated as desired to build a three dimensional photonic crystal of desired geometry.

Layer-by-layer assembly of photonic crystals

A MEMS (Micro Electro Mechanical System) electrostatically operated high voltage switch or relay device is provided. These devices can switch high voltages while using relatively low electrostatic operating voltages. The MEMS device comprises a substrate, a substrate electrode, and one or more substrate contacts. The MEMS device also includes a flexible composite overlying the substrate, one or more composite contacts, and at least one insulator. The switch or relay device is provided overdrive potential through protrusions on the contact surface of the switch or relay contacts. In one embodiment the substrate contacts define protrusions on the contact surface that extend toward the flexible composite contacts. In another embodiment the flexible composite contacts define protrusions on the contact surface that extend toward the substrate contacts.

Overdrive structures for flexible electrostatic switch

A three terminal tunneling device that has a smaller voltage transition between off-current and on-current states and which also has less dependence on the lateral dimensions of the device. The device is a hybrid between a MOS transistor, a gated diode and a tunneling diode. The semiconductor device includes a lightly doped substrate of a first conductivity type. The lightly doped substrate will include a first heavily doped region of a first conductivity type formed in the substrate and a lightly doped layer of a first conductivity type disposed on the substrate and the first heavily doped region. The device also including a gate insulator layer disposed on the lightly doped layer and underlying a portion of the first heavily doped region and a gate electrode that is disposed on the gate insulator layer. Additionally, the device will include a second heavily doped region of a first conductivity formed in the substrate extending into the first heavily doped region of a first conductivity and a heavily doped region of a second conductivity formed in the substrate extending into the lightly doped substrate and spatially isolated from the first heavily doped region.

Low power tunneling metal-oxide-semiconductor (MOS) device

A MEMS (Micro Electro Mechanical System) valve device driven by electrostatic forces is provided. This valve device can provide for fast actuation, large valve force and large displacements while utilizing minimal power. The MEMS valve device includes a substrate having an aperture formed therein, a substrate electrode, a moveable membrane that overlies the aperture and has an electrode element and a biasing element. Additionally, at least one resiliently compressible dielectric layer is provided to insure electrical isolation between the substrate electrode and electrode element of the moveable membrane. In operation, a voltage differential is established between the substrate electrode and the electrode element of the moveable membrane to move the membrane relative to the aperture to thereby controllably adjust the portion of the aperture that is covered by the membrane. Additional embodiments provide for the resiliently compressible dielectric layer to be formed on either or both the substrate electrode and the moveable membrane and provide for either or both the valve seat surface and the valve seal surface. In yet another embodiment the resiliently compressible dielectric layer(s) have a textured surface; either at the valve seat, the valve seal or at both surfaces. In another embodiment of the invention a pressure-relieving aperture is defined within the substrate and is positioned to underlie the moveable membrane. Alternatively, additional embodiments of the present invention provide for MEMS valve arrays driven by electrostatic forces. The MEMS valve array comprises a substrate having a plurality of apertures defined therein. A method for making the MEMS valve device is also provided.

Microelectromechanical flexible membrane electrostatic valve device and related fabrication methods

A MEMS pumping device driven by electrostatic forces comprises a substrate having at least one substrate electrode disposed thereon. Affixed to the substrate is a moveable membrane that generally overlies the at least one substrate electrode. The moveable membrane comprises at least one electrode element and a biasing element. The moveable membrane includes a fixed portion attached to the substrate and a distal portion extending from the fixed portion and being moveable with respect to the substrate electrode. A dielectric element is disposed between the at least one substrate electrode and the at least one electrode element of the moveable membrane to provide for electrical isolation. In operation, a voltage differential is established between the at least one substrate electrode and the at least one electrode element which displaces the moveable membrane relative to the substrate to thereby controllably distribute matter residing between the substrate and the distal portion of the moveable membrane. In a further embodiment the MEMS pumping devices comprise more that two moveable membranes that are configured so as to maximize flow in a desired direction. Additional embodiments include more than one electrode element disposed within the moveable membrane that are capable of individual and sequential biasing to improve overall net flow in the desired flow direction.

Distributed MEMS electrostatic pumping devices

A MEMS apparatus is provided that includes a microelectronic substrate and an elevating structure having a fixed portion attached to the substrate and a distal portion raised from the surface of the substrate. The distal portion of the elevating structure defines at least one zone of attachment. Additionally, the MEMS apparatus comprises a MEMS device attached to the distal portion of the elevating structure at one of the zones of attachment. The attached MEMS device may comprise an electrostatic actuator having a first and second electrode film that are attached to the elevating structure at one of the zones of attachment. In those embodiments in which the MEMS devices comprise an electrostatic actuator the force and movement provided by the actuator may be used to incorporate switches, pumps, valves or other similar MEMS devices.

Microelectromechanical elevating structures

An electromagnetic radiation shutter device driven by electrostatic forces comprises a stationary membrane capable of allowing electromagnetic radiation transmission therethrough, and a first and second flexible membrane comprising an electrode element and at least one biasing element. The first flexible membrane has a fixed portion attached to the underside of the stationary membrane and a distal portion adjacent to the fixed portion and released from the underside of the stationary membrane. The second flexible membrane has a fixed portion attached to the topside of the stationary membrane and a distal portion adjacent to the fixed portion and released from the topside of the stationary membrane. In operation, a voltage differential is established between the electrode element of the first flexible membrane and the electrode element of the second flexible membrane thereby moving the first and second flexible membranes relative to the stationary membrane. In a closed state (i.e. fully activated), the flexible membranes will be generally parallel to the stationary membrane and will be capable of deflecting electromagnetic radiation. In an open state (i.e. no voltage applied), the flexible membranes will generally be fully curled based on biasing in the flexible membranes induced during fabrication and/or imparted by material characteristics.

Electrostatically actuated electromagnetic radiation shutter

A MEMS (Micro Electro Mechanical System) electrostatically operated high voltage variable controlled capacitor device is provided. This device can store high energy over a wide range while using relatively low electrostatic operating voltages. The MEMS device comprises a microelectronic substrate, a substrate signal electrode, and one or more substrate control electrodes. The MEMS device also includes a moveable composite overlying the substrate, having a composite signal electrode, one or more composite control electrodes, and a biasing element. In cross-section, the moveable composite comprises at least one electrode layer and, in most instances, a biasing layer. In length, the moveable composite comprises a fixed portion attached to the underlying substrate and a distal portion moveable with respect to the substrate electrode. The distal and/or medial portions of the moveable composite are biased in position when no electrostatic force is applied. Additionally, the MEMS device comprises insulators to electrically isolate the substrate and electrodes. Applying a variable controlled voltage between the substrate control electrode and moveable composite control electrode, controls the bias of the moveable composite and, in turn, controls the capacitance between the substrate signal electrode and the composite signal electrode. Various embodiments further define the various layering alternatives if the moveable composite, shaping of the electrodes and placement of the electrodes. Additionally, a system for electrostatically controlled variable capacitance comprises a variable controlled voltage source coupled to the control electrodes of the MEMS device of the present invention and a circuit signal electrically coupled to the signal electrodes of the MEMS device. A method of using and a method for making the aforementioned electrostatic MEMS device are also provided.

Electrostatically controlled variable capacitor

A MEMS (Micro Electro Mechanical System) electrostatic device operated with lower and more predictable operating voltages is provided. An electrostatic actuator, an electrostatic attenuator of electromagnetic radiation, and a method for attenuating electromagnetic radiation are provided. Improved operating voltage characteristics are achieved by defining a non increasing air gap between the substrate electrode and flexible composite electrode within the electrostatic device. A medial portion of a multilayer flexible composite overlying the electromechanical substrate is held in position regardless of the application of electrostatic force, thereby sustaining the defined air gap. The air gap is relatively constant in separation from the underlying microelectronic surface when the medial portion is cantilevered in one embodiment. A further embodiment provides an air gap that decreases to zero when the medial portion approaches and contacts the underlying microelectronic surface. A moveable distal portion of the flexible composite is biased to curl naturally due to differences in thermal coefficients of expansion between the component layers. In response to electrostatic forces, the distal portion moves and thereby alters the distance separating the flexible composite from the underlying microelectronic surface. Structures and techniques for controlling bias in the medial portion and the resulting air gap are provided. The electrostatic device may be disposed to selectively clear or intercept the path of electromagnetic radiation. Materials used in the attenuator can be selected to pass, reflect, or absorb various types of electromagnetic radiation. A plurality of electromagnetic attenuators may be disposed in an array and selectively activated in subsets.

Micromachined electrostatic actuator with air gap

A MEMS (Micro Electro Mechanical System) electrostatically operated high voltage switch or relay device is provided. This device can switch high voltages while using relatively low electrostatic operating voltages. The MEMS device comprises a microelectronic substrate, a substrate electrode, and one or more substrate contacts. The MEMS device also includes a moveable composite overlying the substrate, one or more composite contacts, and at least one insulator. In cross section, the moveable composite comprises an electrode layer and a biasing layer. In length, the moveable composite comprises a fixed portion attached to the underlying substrate, a medial portion, and a distal portion moveable with respect to the substrate electrode. The distal and/or medial portions of the moveable composite are biased in position when no electrostatic force is applied. Applying a voltage between the substrate electrode and moveable composite electrode creates an electrostatic force that attracts the moveable composite to the underlying microelectronic substrate. The substrate contact and composite contact are selectively interconnected in response to the application of electrostatic force. Once electrostatic force is removed, the moveable composite reassumes the biased position such that the substrate and composite contacts are disconnected. Various embodiments further define components of the device. Other embodiments further include a source of electrical energy, a diode, and a switching device connected to different components of the MEMS device. A method of using the aforementioned electrostatic MEMS device is provided.

High voltage micromachined electrostatic switch

A MEMS (Micro Electro Mechanical System) electrostatically operated device is provided that can switch high voltages while providing improved arcing tolerance. The MEMS device comprises a microelectronic substrate, a substrate electrode, first and second contact sets, an insulator, and a moveable composite. The moveable composite overlies the substrate and substrate electrode. In cross section, the moveable composite comprises an electrode layer and a biasing layer. In length, the moveable composite comprises a fixed portion attached to the underlying substrate, a medial portion, and a distal portion moveable with respect to the substrate electrode. Each contact set has at least one composite contact attached to the moveable composite, and preferably at least one substrate contact attached to the substrate. One of the contact sets is closer to the composite distal portion. The distal and/or medial portions of the moveable composite are biased in position when no electrostatic force is applied. Applying a voltage between the substrate electrode and moveable composite electrode creates an electrostatic force that attracts the moveable composite to the underlying substrate. The first and second contact sets are electrically connected when the distal portion of the moveable composite is attracted to the substrate. Once electrostatic force is removed, the moveable composite reassumes the biased position such that the first and second contact sets are disconnected in a sequence to minimize arcing. Various embodiments and methods of using the electrostatic MEMS device are provided.

Arc resistant high voltage micromachined electrostatic switch

A noise suppressor includes an input transducer and an output transducer adapted to be located in an ear canal. A housing is provided to support the transducers in the ear canal, and the housing provides an acoustically unobstructed passage from the entrance of the ear canal to the ear drum. The input transducer generates electrical signals in response to sound pressure waves entering the ear canal, and a portion of the electrical signal is processed to generate an inverse noise signal which is applied to the output transducer. Accordingly, the output transducer produces inverse noise pressure waves in order to reduce an undesired noise portion of the sound pressure waves reaching the ear drum. The sound pressure waves also reach the ear drum without significant alteration.

Active noise supressors and methods for use in the ear canal

A microelectromechanical transducer including a plurality of parallel electrically conductive strips maintained in closely spaced relation by a plurality of spacers can generate useful displacements and forces. The transducer can be strengthened by arranging the conductive strips in cells surrounded by unidirectional cell stiffening members and unidirectional displacement limiting members. The unidirectional cell stiffening members may include notches. The unidirectional displacement limiting members may include unidirectional buckling straps or flexible arches. The cells of electrically conductive strips can be organized in modular or fractal arrays.

Growing community of inventors

Pittsboro, NC, United States of America

Scott Halden Goodwin-Johansson