135results about "Variable capacitor structural combinations" patented technology

A method, device and circuit which applies an electrostatic repulsion pushing force to a MEM switch armature during an opening process. The repulsive force adds to the spring restoration force on the armature, increasing the opening speed of the switch and aids in overcoming stiction effects. The inventive switch includes a contact electrically connected to a first terminal of the switch. A throw is electrically connected to a second terminal of the switch. Finally, a mechanism is provided for opening the switch by electrostatically causing the throw to disengage the contact. In the illustrative implementation, the mechanism for opening the switch includes a first charge storage structure mounted on the throw and a second charge storage structure mounted in proximity to the first charge storage structure. When charges are applied between the first and the second charge storage structures, a force of repulsion is created or a force of attraction is created depending on the polarity of the potential.

MEMS-based, computer system, clock generation and oscillator circuits and LC-tank apparatus for use therein are provided and which are fabricated using a CMOS-compatible process. A micromachined inductor (L) and a pair of varactors (C) are developed in metal layers on a silicon substrate to realize the high quality factor LC-tank apparatus. This micromachined LC-tank apparatus is incorporated with CMOS transistor circuitry in order to realize a digital, tunable, low phase jitter, and low power clock, or time base, for synchronous integrated circuits. The synthesized clock signal can be divided down with digital circuitry from several GHz to tens of MHz—a systemic approach that substantially improves stability as compared to the state of the art. Advanced circuit design techniques have been utilized to minimize power consumption and mitigate transistor flicker noise upconversion, thus enhancing clock stability.

A MEMS module is provided comprising at least one MEMS device adhesively bonded to a substrate or wafer, such as a CMOS die, carrying pre-processed electronic circuitry. The at least one MEMS device, which may comprise a sensor or an actuator, may thus be integrated with related control, readout/signal conditioning, and/or signal processing circuitry.

An example of a method pursuant to the invention comprises the adhesive bonding of a pre-processed electronics substrate or wafer to a layered structure preferably in the form of a silicon-on-insulator (SOI) substrate. The SOI is then bulk micromachined to selectively remove portions thereof to define the MEMS device. Prior to release of the MEMS device, the device and the associated electronic circuitry are electrically interconnected, for example, by wire bonds or metallized vias.

A Micro Electro-Mechanical System (MEMS) acceleration sensing device formed of a silicon substrate having a substantially planar surface; a pendulous sensing element having a substantially planar surface suspended in close proximity to the substrate planar surface; a flexure suspending the sensing element for motion relative to the substrate planar surface, the flexure having a both static geometric centerline and a dynamic centerline that is offset from the static geometric centerline; and a metal electrode positioned on the substrate surface for forming a capacitor with the pendulous sensing element, the metal electrode being positioned as a function of the dynamic centerline of the flexure.

The present invention discloses a Micro-Electro-Mechanical systems (MEMS) device suitable for use in a range of applications from DC, such as switching electrical signal lines, to RF applications such as tunable capacitors and switches. In an embodiment of the invention, the device comprises a bottom substrate and a top substrate separated at a fixed distance from each other. Disposed between the substrates is a flexible S-shaped membrane having an electrode or an electrically conducting electrode layer with one end attached to the top substrate and the other end in contact with the bottom substrate. An electrically conducting contact block is attached to the underside of the membrane actuator for short circuiting a signal line when the switch is in the closed position. When a voltage is applied between the membrane and an electrode layer on the bottom substrate, the membrane is induced by electrostatic force to deflect in a rolling wave-like motion such that the contact block is displaced into contact with the signal line. The device can be actively opened when a voltage is applied between the membrane actuator and a electrode layer on the top substrate causing the contact block to displace upward breaking contact with the signal line. The MEMS switching device is applicable for use in a switch matrix board for automatically switching telephone lines or in RF applications in the form of a tunable capacitor.

One embodiment of the present invention relates to a variable capacitor that operates without moving mechanical parts. In this capacitor electrically conductive electrodes are separated by an enclosed chamber filled with an electrically conductive material. The electrically conductive material can freely vary its position within the chamber. The capacitance of the device will vary as position of the conductive material changes due to external mechanical motion (ex: rotation vibration, etc.) of the device. Other embodiments of this device are also disclosed.

A tunable filter having a fixed substrate, a first and second plate comprising a high-temperature superconductor material on the fixed substrate, a movable substrate, a mechanical driver attached to the fixed substrate and the movable substrate, a floating plate comprising a high-temperature superconductor material on the fixed substrate wherein the floating plate, the first plate, and the second plate define a gap, and wherein the gap is varied by length changes in the mechanical driver is provided.

Rather than increasing the mass of the structure, the structure in a sensor system suspends its substrate from some mechanical ground. Motion of the substrate relative to the mechanical ground thus provides the movement information. To those ends, the sensor system includes a base, a substrate, and a flexible member suspended from at least a portion of the substrate. At least a portion of the flexible member is capable of moving relative to at least a portion of the substrate. In addition, the flexible member is secured to the base, thus causing the substrate to be movable relative to the base. Moreover, the mass of the substrate is greater than the mass of the flexible member. The substrate and flexible member are configured to interact to produce a motion signal identifying movement of the base.

A method of fabricating micro-electromechanical switches (MEMS) integrated with conventional semiconductor interconnect levels, using compatible processes and materials is described. The method is based upon fabricating a capacitive switch that is easily modified to produce various configurations for contact switching and any number of metal-dielectric-metal switches. The process starts with a copper damascene interconnect layer, made of metal conductors inlaid in a dielectric. All or portions of the copper interconnects are recessed to a degree sufficient to provide a capacitive air gap when the switch is in the closed state, as well as provide space for a protective layer of, e.g., Ta/TaN. The metal structures defined within the area specified for the switch act as actuator electrodes to pull down the movable beam and provide one or more paths for the switched signal to traverse. The advantage of an air gap is that air is not subject to charge storage or trapping that can cause reliability and voltage drift problems. Instead of recessing the electrodes to provide a gap, one may just add dielectric on or around the electrode. The next layer is another dielectric layer which is deposited to the desired thickness of the gap formed between the lower electrodes and the moveable beam that forms the switching device. Vias are fabricated through this dielectric to provide connections between the metal interconnect layer and the next metal layer which will also contain the switchable beam. The via layer is then patterned and etched to provide a cavity area which contains the lower activation electrodes as well as the signal paths. The cavity is then back-filled with a sacrificial release material. This release material is then planarized with the top of the dielectric, thereby providing a planar surface upon which the beam layer is constructed.

The present invention relates to a chip package that includes a semiconductor device and at least one micro electromechanical structure (MEMS) such that the semiconductor device and the MEMS form an integrated package. One embodiment of the present invention includes a semiconductor device, a first MEMS device disposed in a conveyance such as a film, and a second MEMS device disposed upon the semiconductor device through a via in the conveyance.

The present invention also relates to a process of forming a chip package that includes providing a conveyance such as a tape automated bonding (TAB) structure, that may hold at least one MEMS device. The method is further carried out by disposing the conveyance over the active surface of the device in a manner that causes the at least one MEMS to communicate electrically to the active surface. Where appropriate, a sealing structure such as a solder ring may be used to protect the MEMS.

A torsion spring for an electro-mechanical switch is presented. The torsion spring comprises a set of tines including at least one tine extending from the free end of the armature of a switch. A terminus portion is rotatably suspended between the tines, and includes a conducting transmission line, at least a portion of which is exposed for electrical contact. The conducting transmission line has a length selected such that the exposed portion of the transmission line forms a circuit between the input and output of the micro-electro-mechanical switch when the micro-electro-mechanical switch is urged into a closed position, with the terminus portion rotating via the tines to form a conformal connection between the exposed portion of the conducting transmission line and the input and output of the switch, thus optimizing the electrical flow therebetween. The switch is also applied to MEMS devices.

An RF-MEMS switch includes a plurality of movable electrodes disposed with a space provided therebetween in the direction of RF signal conduction of an RF signal-conducting unit which is provided above the RF signal-conducting unit. A movable electrode displacing unit for displacing all the movable electrodes at the same time in the same direction towards or away from the RF signal-conducting unit is provided. The electrical length of the RF signal-conducting unit sandwiched between the movable electrodes is set such that the amplitude of a combined signal including signals reflected in positions of the RF signal-conducting unit facing the movable electrodes is less than the amplitude of each of reflected signals reflected in positions of the RE signal-conducting unit facing the movable electrodes when the movable electrodes are displaced away from the RF signal-conducting unit and signal conduction of the RF signal-conducting unit is switched on.

The invention is a tunable RF MEMS switch developed with a BST dielectric at the contact interface. BST has a very high dielectric constant (>300) making it very appealing for RF MEMS capacitive switches. The tunable dielectric constant of BST provides a possibility of making linearly tunable MEMS capacitive switches. The capacitive tunable RF MEMS switch with a BST dielectric is disclosed showing its characterization and properties up to 40 GHz.

There is provided a variable device circuit according to the present invention, including: a substrate; at least one movable switch device formed on a first principal surface of the substrate; at least one fixed capacitor device formed on the first principal surface of the substrate; at least one variable capacitor device formed on the first principal surface of the substrate; at least one variable inductor device formed on the first principal surface of the substrate; and wiring lines for electrically connecting the devices to one another, the wiring lines being formed on the first principal surface of the substrate; wherein electrical connections among the devices can be selected by operation of the movable switch device, whereby achieving stable, low-loss circuit characteristics with lower manufacturing cost.

A variable capacitance element includes a coplanar line or signal conduction and a movable body, which are vertically displaced through a supporting bar and which are provided on a substrate. A movable electrode is provided between a first driving electrode and second and third driving electrodes which are movable electrodes. Voltage is applied between the movable electrodes, such that one of the movable electrodes is pressed against the coplanar line through a dielectric film. Thus, high frequency signals conducting through the coplanar line are shut off. When voltage is applied between the other electrodes, the movable electrode and the dielectric film are moved apart from the coplanar line. Thus, high frequency signals are conducted through the coplanar line.

A switch comprises voltage applying means for providing direct current potentials to first to third beams arranged with a spacing slightly distant one from another, and electrodes for inputting/outputting signals to/from the beams. By controlling the direct current potential provided to the beam, an electrostatic force is caused to thereby change the beam positions and change a capacitance between the beams. By causing an electrostatic force between the first and second beams and moving the both beams, the first and second beams can be electrically coupled together at high speed. Also, an electrostatic force is caused on the third beam arranged facing to the first and second beams, to previously place it close to the first and second beams. When the electrostatic force is released from between the first and second beams, the second beam moves toward the third beam thereby releasing the first and second beams of an electric coupling.