Abstract: The present invention provides a capacitive RF-MEMS device comprising a vertically integrated decoupling capacitor (14). The decoupling capacitor (14) therefore does not take extra area. Furthermore, the RF-MEMS according to the invention needs less interconnects, which also saves space and which reduces the series inductance/resistance in the RF path.

Abstract: A circuit component has an elastically deformable first structure, a second structure, and a support structure coupling the first and second structures, wherein the first structure can be variably deformed in response to a variable force, to provide either a variable capacitor or a variable tank circuit having a variable capacitor and an inductor. In one particular embodiment, a piezoelectric element is laminated to the surface of the first elastically deformable structure thereby providing the capability to deform the first structure. A method of making a circuit component includes forming an elastically deformable first structure, forming a second structure, and joining the first and second structures, to provide either a variable capacitor or a variable tank circuit having a variable capacitor and an inductor.

Abstract: Micro-electro-mechanical system (MEMS) variable capacitors and actuation components and related methods are provided. A MEMS variable capacitor can include first and second feed lines extending substantially parallel to one another. Further, MEMS variable capacitors can include first and second capacitive plates being spaced apart from the first and second feed lines. The first and second capacitive plates can be separately movable with respect to at least one of the first and second feed lines for varying the capacitance between the first and second feed lines over a predetermined capacitance range.

Abstract: An actuator includes a substrate, a fixed electrode provided on a major surface of the substrate, a movable beam opposed to the major surface and held above the substrate with a gap thereto, and a dielectric film provided between the fixed electrode and the movable beam. The dielectric film is made of aluminum nitride oriented along c-axis with an orientation full width at half maximum of 4.6 degrees or less.

Abstract: The devices presented herein are capacitive sensors with single crystal silicon on all key stress points. Isolating trenches are formed by trench and refill forming dielectrically isolated conductive silicon electrodes for drive, sense and guards. For pressure sensing devices according to the invention, the pressure port is opposed to the electrical wire bond pads for ease of packaging. Dual-axis accelerometers measuring in plane acceleration and out of plane acceleration are also described. A third axis in plane is easy to achieve by duplicating and rotating the accelerometer 90 degrees about its out of plane axis Creating resonant structures, angular rate sensors, bolometers, and many other structures are possible with this process technology. Key advantages are hermeticity, vertical vias, vertical and horizontal gap capability, single crystal materials, wafer level packaging, small size, high performance and low cost.

Abstract: A variable capacitance element of the invention includes: a columnar vibrator formed inside a cylindrical hole of a supporting wall; a first circular driving electrode disposed above the columnar vibrator; a first circular capacitive electrode disposed in the middle of the columnar vibrator; a second circular driving electrode disposed on the periphery of the cylindrical hole of the supporting wall; and a second circular capacitive electrode disposed on an inner side surface of the supporting wall. An electrostatic force is increased or decreased sequentially in the circumferential direction of the second driving electrode that is divided into four parts by sequentially increasing or decreasing the driving voltage in the circumferential direction of the second driving electrode. As a result, the columnar vibrator is rotated to change the electrostatic capacitance between the first capacitive electrode and the second capacitive electrode.

Abstract: A method for manufacturing a semiconductor physical quantity sensor including a support substrate, a movable electrode, a fixed electrode is provided. The method includes the steps of: preparing a multi-layered substrate; forming a compression stress layer on a part of a surface of the semiconductor layer; forming a trench in the semiconductor layer; and releasing the movable electrode from the substrate by removing the insulation film. In the step of releasing, the part of the semiconductor layer, on which the compression stress layer is disposed, is cambered by the compression stress toward a direction apart from the substrate.

Abstract: The variable capacitance (1) according to the invention is based on a novel principle: a dielectric fluid (20) is placed in the air gap constituted by two capacitor electrodes (12, 14), the fluid being able to be displaced in a direction and outside the cavity (10) formed between said two electrodes (12, 14). Advantageously, the dielectric fluid (20) is displaced according to the principle of communicating vessels, with the presence of a second cavity (30) in fluidic relation with the first cavity. Actuation electrodes (46, 48) in the second cavity (30) induce the deflection of a membrane (44) in order to modify the relative heights of fluidic liquid in the two cavities (10, 30).

Abstract: A micro-electro-mechanical system varactor. The varactor includes a substrate, a lower bias conductor partially overlaying the substrate, a first signal conductor partially overlaying the substrate, a dielectric layer at least partially overlaying the first signal conductor, a support structure coupled to the substrate, and a flexible structure coupled to the support structure. The flexible structure is suspended over the substrate, includes an upper bias conductor overlaying at least part of the lower bias conductor and a top conductor overlaying at least part of the first signal conductor, configured to deflect in response to a bias voltage applied between the upper bias conductor and the lower bias conductor, and configured for separation between the top conductor and the dielectric layer by a varying separation distance dependent upon the bias voltage.

Abstract: A method of manufacturing capacitive elements for a capacitive device which comprises one or more layers is provided. At least one layer is etched from a first surface to a second surface thereof to form two sections of the layer, such that the sections are movable relative to one another, and such that a wall extending from the first surface to the second surface is formed on each of the two sections, the walls defining a gap therebetween. An etching step forms multiple recesses in each wall such that multiple capacitive elements are defined between adjacent recesses, the capacitive elements of one wall being offset from those of the other wall when the sections are stationary with respect to one another. A corresponding capacitive device is also provided.

Abstract: A lower movable electrode 35, having line sections 35a, 35a on both ends and a capacitor section 35b in the center, and an upper movable electrode 37, having line sections 37a, 37a on both ends and a capacitor section 37b in the center, are placed so that the capacitor sections 35b, 37b face each other, and drive electrodes of lower-movable-electrode actuators 27a, 27b, 27c, 27d driving the lower movable electrode 35 and upper-movable-electrode actuators 29a, 29b, 29c, 29d driving the upper movable electrode 37 are electrically separated from the lower movable electrode 35 and upper movable electrode 37. These actuators 27a to 27d and/or 29a to 29d move the lower movable electrode 35 and/or upper movable electrode 37 to adjust the distance between both capacitor sections 35b, 37b, and control the electrostatic capacity.

Abstract: A micro-electromechanical variable capacitor with first and second capacitor plates spaced apart to define a gap therebetween. The first plate has two control electrodes and an active electrode. The second plate is movable relative to first plate when a voltage is applied to produce a potential difference across the control electrode and the second capacitor plate. This has the effect of varying the capacitance of the capacitor. The facing surface of at least one of the plates is formed in such a way that it has a roughened surface. The degree of roughness is sufficient to prevent the facing surfaces adhering together through stiction.

Abstract: A charge storage device having a capacitance that is variable by alteration of the relative permittivity of the dielectric positioned between conductive electrodes within the device. The device consists of two conductive plates sandwiching a conductive grid, typically embedded within a dielectric material. Charging the grid with a negative or positive potential changes the value of the dielectric constant (the relative permittivity) and thereby changes the capacitance of the device.

Abstract: A device for varying the capacitance of an electronic circuit is disclosed. The device comprises a flexible membrane located above the electronic circuit, a metal layer connected to the flexible membrane, and bias circuitry located above the membrane. Variation of the capacitance of the electronic circuit is obtained by pulling the membrane upwards by means of the bias circuitry. The disclosed device provides a sizeable capacitance variation and high Q factor, resulting in overall low filter insertion loss. A nearly constant group delay over a wide operating bandwidth is also obtained.

Abstract: A MEMS tunable capacitor and method of fabricating the same, includes a plurality of fixed charge plates on a substrate, the plurality of fixed charge plates having a same height, being arranged in a shape of comb-teeth and being electrically connected to one another, a capacitor dielectric layer covering the plurality of fixed charge plates, a movable charge plate structure spaced apart from the capacitor dielectric layer, and arranged on the plurality of fixed charge plates, wherein the movable charge plate structure includes a plurality of movable charge plates arranged corresponding the plurality of fixed charge plates, and an actuator connected to the movable charge plate structure allowing the movable charge plate structure to move in a horizontal direction.

Abstract: A high precision microelectromechanical capacitor with programmable voltage source includes a monolithic MEMS device having a capacitance actuator, a trim capacitor, and a high precision, programmable voltage source. The trim capacitor has a variable capacitance value, preferably for making fine adjustments in capacitance. The capacitance actuator is preferably mechanically coupled to and electrically isolated from the trim capacitor and is used to control the capacitance value of the trim capacitor. The capacitance adjustment of the trim capacitor is non-destructive and may be repeated indefinitely. The trim capacitor may be adjusted by mechanically changing the distance between its electrodes. The programmable voltage source provides a highly accurate and stable output voltage potential corresponding to control signals for controlling the capacitance actuator.

Abstract: According to one aspect, the subject matter described herein includes a MEMS fixed capacitor and a method for fabricating the MEMS fixed capacitor. The MEMS fixed capacitor can include a first stationary, capacitive plate on a substrate. Further, the MEMS fixed capacitor can include a non-conductive, stationary beam suspended above the substrate. The MEMS fixed capacitor can also include a second stationary, capacitive plate spaced a predetermined distance from the first stationary, capacitive plate for producing a predetermined capacitance between the capacitive plates.

Abstract: A capacitive transducer includes a substrate having a first surface and a second surface. The first surface of the substrate defines a first plane. The substrate has a cavity with an interior peripheral edge. The cavity extends between the first surface and the second surface. A body is provided that has an exterior peripheral edge. The body is parallel to the first plane and at least partially blocking the cavity. The body is connected to the substrate by resilient hinges such that, upon the application of a force, the body moves perpendicular to the first plane. A first set of comb fingers is mounted to the substrate. The first set of comb fingers is connected to a first electrical connection. A second set of comb fingers is mounted to the body and extends past the exterior peripheral edge of the body. The second set of comb fingers is connected to a second electrical connection that is isolated from the first connection.

Abstract: A variable capacitor includes a supporting substrate and a plurality of variable capacitance elements, and bias lines. The plurality of variable capacitance elements is formed on the supporting substrate, each of which is composed of a lower-laid first electrode layer, an upper-laid second electrode layer, and a dielectric layer sandwiched therebetween whose dielectric constant changes with direct current bias voltage. In the variable capacitance elements which are adjacent to each other, the second electrode layer of a first variable capacitance element and the first electrode layer of a second variable capacitance element are electrically connected in series with each other. The bias lines each include at least one of resistance component and inductance component for applying the direct current bias voltage. The variable capacitance elements are each connected to the bias lines.

Abstract: A method is provided of continuously varying the capacitance of a MEMS varactor having a cantilever assembly mounted on a base portion, the cantilever assembly having a first capacitance plate and a dielectric element mounted thereon, and the base portion having a second capacitance plate mounted thereon. The method includes applying a first actuation voltage to deform the cantilever assembly until the dielectric element contacts the second capacitance plate leaving a gap therebetween, and applying a second actuation voltage larger than the first actuation voltage to further deform the cantilever assembly to reduce the gap between the dielectric element and the second capacitance plate.

Abstract: A heat-sensitive apparatus includes a substrate with a top surface, one or more bars being rotatably joined to the surface and having bimorph portions, and a plate rotatably joined to the surface and substantially rigidly joined to the one or more bars. Each bimorph portion bends in response to being heated. The one or more bars and the plate are configured to cause the plate to move farther away from the top surface in response to the one or more bimorph portions being heated.

Abstract: According to one embodiment a microelectromechanical (MEMS) switch is disclosed. The MEMS switch includes a substrate, a plurality of actuation electrodes mounted on the substrate, a plurality of bottom electrodes mounted on the substrate, a capacitor having subcomponents mounted on the two or more bottom electrodes and a top bendable electrode mounted on the substrate. The top electrode collapses a first magnitude towards the actuation electrodes whenever a first voltage is applied to one or more of the actuation electrodes and collapses a second magnitude towards the actuation electrodes whenever a second voltage is applied to the actuation electrodes.

Abstract: A digital variable capacitor package is provided as having a ground plane disposed on predetermined portion of the top surface of a substrate. An elongated signal electrode may also be disposed on the substrate and including a first end defining an input and a second end extending to a substantially central region of the top surface of the substrate. This elongated signal electrode is disposed to be electrically isolated from the ground plane. A number of elongated cantilevers are disposed on the substrate and each include first ends coupled to the second end of the signal electrode and each further include second ends suspended over different predetermined portions of the ground plane. In operation, one or more of the cantilevers may be actuated to move portion thereof into close proximity to the ground plane for providing one or more discrete capacitance values.

Abstract: A capacitive transducer of multi-layer construction includes two rotor plates supported by flexible springs, the plates being spaced apart and rigidly connected by a stem. One rotor plate my be used as either a pickup electrode or a grounded target electrode for determining position, displacement, or load force. The second rotor plate may be used for electrostatic actuation without interfering with or destroying circuitry associated with the first rotor plate. A number of improvements are disclosed including a hollow rotor plate structure for reduced moving mass, buckling resistant features for the springs, improved spring anchor joint design for reduced creep and hysteresis, and material selection and matching for reduced thermal sensitivity.

Abstract: A capacitance detection apparatus includes a detection electrode for detecting approach of an object on the basis of a change of capacitance, a calculating circuit for calculating a value associated with the capacitance change, a judging circuit for judging whether the calculated value is a normal or initial value calculated after or before a predetermined period of time lapse from a start time of the capacitance detection apparatus, an initial reference value-determining circuit for determining an initial reference value, a difference calculating circuit for calculating a difference between the normal value and a value calculated earlier than a time when the normal value is calculated by the predetermined period of time or longer or between the initial value and the initial reference value, and a determining circuit for determining whether the object is approaching by comparing the difference with a predetermined threshold value.

Abstract: A vacuum capacitor including an insulating cylinder having first and second ends which are opposite to each other. A stationary-side flange is installed to the first end of the insulating cylinder. A stationary electrode supporting plate is installed to an inner surface side of the stationary-side flange. A movable-side flange is installed to the second end of the insulating cylinder. A movable electrode supporting plate is installed to an inner surface side of the movable-side flange through an electrostatic capacity adjusting screw and movable relative to the stationary electrode supporting plate by turning of the electrostatic capacity adjusting screw. Additionally, a diaphragm is sealingly connected between the movable-side flange and the movable electrode supporting plate, the diaphragm having corrugation and defining a vacuum side and an atmospheric side in the vacuum capacitor.

Abstract: A MEMS tunable capacitor and method of fabricating the same, includes a plurality of fixed charge plates on a substrate, the plurality of fixed charge plates having a same height, being arranged in a shape of comb-teeth and being electrically connected to one another, a capacitor dielectric layer covering the plurality of fixed charge plates, a movable charge plate structure spaced apart from the capacitor dielectric layer, and arranged on the plurality of fixed charge plates, wherein the movable charge plate structure includes a plurality of movable charge plates arranged corresponding the plurality of fixed charge plates, and an actuator connected to the movable charge plate structure allowing the movable charge plate structure to move in a horizontal direction.

Abstract: An adjustable capacitor has a tubular housing including a first insulating section and a second section having a conductive portion at the exterior surface thereof forming an external terminal. An external terminal conductor is joined to an exterior terminal portion of the capacitor housing, for connecting the terminal to an external circuit. The external terminal conductor has a thickness, over its length, not less than a thickness of the housing. The external terminal conductor can have a width greater than the width of the housing, and a thickness not appreciably less than the average thickness of the housing. The external terminal conductor can be press-fitted onto the housing to form a secure electrical connection, attached by another suitable means, or integrally formed therewith.

Abstract: A variable capacitance capacitor has a plurality of variable capacitance elements, using a thin-film dielectric layer whose dielectric constant varies with voltage application, connected in series with one another between the high-frequency signal input and output terminals. The first bias lines belonging to a high-potential side and the second bias lines belonging to a low-potential side, in terms of voltage application, are connected, alternately, to electrodes of the variable capacitance elements connected one another and electrodes in the array of the series-connected variable capacitance elements connected respectively to the input terminal and the output terminal.

Abstract: Capacitors (10,20,40,50,70,80) having a fluid dielectric material that is transported or undergoes a phase change are disclosed. The dielectric medium change results in a change in the total dielectric constant of the material between the electrodes (12, 14, 72, 74, 81, 82), thus changing the capacitance of the capacitors. Transporting or phase changing the dielectric fluids into and out of a the electric field of the capacitor, changes the effective dielectric constant and the capacitance of the capacitor.

Abstract: A MEMS tunable capacitor with angular vertical comb-drive (AVC) actuators is described where high capacitances and a wide continuous tuning range is achieved in a compact space. The comb fingers rotate through a small vertical angle which allows a wider tuning range than in conventional lateral comb drive devices. Fabrication of the device is straightforward, and involves a single deep reactive ion etching step followed by release and out-of-plane assembly of the angular combs.

Abstract: The disclosure describes a variable capacitor device, which is formed by a linear motor and a variable capacitor having at least one stator electrode and a movable electrode. A piezoelectric transducer of the linear motor is frictionally coupled to the movable electrode. Application of electrical signals to the piezoelectric transducer of the linear motor produces a motion of the surface of the piezoelectric transducer. The frictional coupling between the piezoelectric transducer surface and the movable electrode transmits a fraction of piezoelectric transducer motion to the movable piston electrode thereby changing the capacity of the variable capacitor. The amount and sign of the capacitance change is selectable by the operator through control of the electrical signals applied to the piezoelectric transducer.

Abstract: A capacitive transducer of multi-layer construction includes two rotor plates supported by flexible springs, the plates being spaced apart and rigidly connected by a stem. One rotor plate my be used as either a pickup electrode or a grounded target electrode for determining position, displacement, or load force. The second rotor plate may be used for electrostatic actuation without interfering with or destroying circuitry associated with the first rotor plate. A number of improvements are disclosed including a hollow rotor plate structure for reduced moving mass, buckling resistant features for the springs, improved spring anchor joint design for reduced creep and hysteresis, and material selection and matching for reduced thermal sensitivity.

Abstract: Tunable capacitors (10, 20, 30, 40) have a dielectric material (16, 26, 36, 42) between electrodes, which dielectric material comprises an insulating material (17, 27, 37, 42) and electrically conductive material, (18, 28, 38, 48) e.g., conductive nanoparticulates, dispersed therein. In certain cases, enhanced tune-ability is achieved when the dielectric material comprises elongated nanoparticulates (38). Further enhanced tune-ability may be achieved by aligning elongated particulates in an electrode-to-electrode direction. Nanoparticulates may be produced by heating passivated nanoparticulates. Passivated nanoparticulates may be covalently bound within a polymeric matrix. High bias potential device structures can be formed with preferential mobilities.

Abstract: Electrically tunable electromagnetic bandgap (“TEBG”) structures using a ferroelectric thin film on a semiconductor substrate, tunable devices that include such a TEBG structure, such as a monolithic microwave integrated circuit (“MMIC”), and a method producing such a TEBG structure are disclosed. The present invention provides a semiconductive substrate having an oxide layer, a first conductive layer positioned on the oxide layer, a ferroelectric layer covering the first conductive layer, and a second conductive layer positioned on a surface of the tunable ferroelectric layer. The use of the ferroelectric layer, which have a DC electric field dependent permittivity, enables a small size, tunable EBG structure.

Abstract: A variable position sensor has a stationary portion and a moveable portion. A plurality of plates are positioned on one of the members with the surfaces of the plates forming segments of a larger surface. A single plate is mounted on the other of the two members. One pole of an electric potential is applied to a first of the plurality of plates on the one member and the second pole of the electric potential is applied to the single plate on the other member. Similarly a pole of an electric potential is separately applied to each of the other of the parallel plates and to the one plate. When the one plate is positioned adjacent one of the plurality of plates a capacitance is formed between the adjacent plates, and by detecting the capacitance the position of the one plate can be determined.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: A variable capacitor includes a stator and a rotor rotatably supported by a cover relative to the stator. The stator includes a first stator electrode of two or more layers and a second stator electrode of two or more layers in the interior of a dielectric substrate. The first stator electrode is connected to a first external electrode and the second stator electrode is connected to a second external electrode. The rotor includes a rotor electrode of two pieces opposing the stator electrodes, and capacitances are defined in the areas of overlap of the rotor electrode and stator electrodes. The capacitances are adjustable to extremely small levels.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: A detector assembly including a support element, a first capacitor plate and a second capacitor plate. The support element is configured to attach the detector assembly to a chamber wall that separates a lower pressure region and a higher pressure region. A surface of the second capacitor plate is spaced apart from a surface of the first capacitor plate to define a capacitor gap. The first capacitor plate is positioned to be inside the lower pressure region when the detector assembly is attached to the chamber wall. The second capacitor plate is supported by the support element through insulating couplings. The detector assembly also includes a means for reducing mechanical load on the insulating couplings between the second capacitor plate and the support element. The reduced mechanical load includes load caused by a pressure difference between the lower and higher pressure regions.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: A variable capacitor is provided such that it is possible to make nonlinear distortion small and use at high power handling capability, and such that a variable rate of capacitance is not influenced by a high-frequency voltage substantially. A variable capacitor is used by changing capacitance through application across electrodes of direct current voltage and high-frequency voltage. When an effective voltage value of high-frequency voltage is within a range of voltage values of direct current voltage, there is substantially no fluctuation caused by application of high-frequency voltage with respect to a change of capacitance caused by application of direct current. Since it is possible to decrease susceptibility to the high-frequency voltage of the variable capacitor, it is possible to obtain a variable capacitor such that nonlinear distortion is small and power handling capability is high.

Abstract: A tunable element in the microwave frequency range is described that may include one or more tunable elements that are directly digitally controlled by a digital bus connecting a digital control circuit to each controlled element. In particular, each digital signal is filtered by a digital isolation technique so that the signal reaches the tunable elements with very low noise. The low noise digital signals are then converted to analog control voltages. The direct D/A conversion is accomplished by a special D/A converter which is manufactured as an integral part of a substrate. This D/A converter in accordance with the invention may consist of a resistor ladder or a directly digitally controlled capacitor. The direct digitally controlled capacitor may be a cantilevered type capacitor having multiple separate electrodes or sub-plates representing binary bits that may be used to control the capacitor.

Abstract: A three-dimensional micro electro-mechanical (MEMS) variable capacitor is described wherein movable comb electrodes of opposing polarity are fabricated simultaneously on the same substrate are independently actuated. These electrodes are formed in an interdigitated fashion to maximize the capacitance of the device. The electrodes are jointly or individually actuated. A separate actuation electrode and a ground plane electrode actuate the movable electrodes. The voltage potential between the two electrodes provides a primary mode of operation of the device. The variation of the sidewall overlap area between the interdigitated fingers provides the expected capacitance tuning of the device. The interdigitated electrodes can also be attached on both ends to form fixed-fixed beams. The stiffness of the electrodes is reduced by utilizing thin support structures at the ends of the electrodes. The three dimensional aspect of the device avails large surface area.

Abstract: Micro-Electro-Mechanical System (MEMS) Variable Capacitor Apparatus and Related Methods. According to one embodiment, a MEMS variable capacitor is provided. The variable capacitor can include first and second electrodes being spaced apart, and at least one of the electrodes being movable when a voltage is applied across the first and second electrodes. The variable capacitor can also include a first conductive plate attached to and electrically isolated from the first electrode. Furthermore, the variable capacitor can include a second conductive plate attached to the second electrode and spaced from the first conductive plate for movement of at least one of the plates with respect to the other plate upon application of voltage across the first and second electrodes to change the capacitance between the first and second plates.

Abstract: An ultra miniature high temperature capacitive inductive pressure transducer is fabricated by MEMS techniques. The transducer consists of two separated pieces of silicon which form the plates of the capacitor, one of which plate is micromachined in such a way to allow a controlled deflection with pressure. The gap between the two capacitive plates is determined by an extending rim on one of the two plates. The two pieces of silicon are subsequently fusion bonded, leading a very small gap between the two plates. An inductor is formed on the top surface of one of the pieces of silicon by sputtering metal in a spiral like fashion on the back side of the non-micromachined plate.

Abstract: An economical, force-sensing “stiff” capacitive joystick includes a user-manipulable handle coupled to an electrically conductive drive plate, and an electrically conductive surface spaced apart from the drive plate. In the preferred embodiment, one or both of the drive plate and the conductive surface are segmented to produce multiple capacitive sensing elements, such that a force applied to the handle causes a slight deflection of the drive plate, enabling the force to be computed in at least two dimensions through changes detectable in the capacitive sensing elements. One or more electrical controls may be provided on the handle to accommodate different functions. For convenient construction, the electrically conductive drive plate is non-segmented, and the electrically conductive surface forms part of a printed-circuit board having a segmented pattern.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: A charge control circuit for controlling a micro-electromechanical device having a variable capacitance is disclosed. In one embodiment, a charge storage device is configured to store a charge amount. A switch circuit is configured to control the variable capacitance of the micro-electromechanical device by sharing the charge amount between the charge storage device and the micro-electromechanical device to equalize the charge storage device and the micro-electromechanical device to a same voltage.

Abstract: 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.