Abstract: Measurement apparatus, for generating a first output signal indicative of a measurand, comprises: a first oscillator circuit and a second oscillator circuit, each oscillator circuit being arranged to generate a respective oscillating output signal and comprising at least a respective first component having a property determining a respective output frequency of the respective oscillating output signal; a sensor for sensing said measurand, the sensor comprising said first component of the first oscillator circuit, said property of said first component of the first oscillator circuit being dependent upon said measurand; and circuitry arranged to receive said oscillating output signals and generate said first output signal, said first output signal being indicative of a number of cycles of one of the first and second oscillating output signals in a time period determined by a period of the other of said first and second oscillating output signals.

Abstract: A magnetic field detection device includes a magnetic field detection element, a modulation coil, and a demodulator. The magnetic field detection element has a sensitivity axis in a first direction. The modulation coil is configured to apply, to the magnetic field detection element, an alternating current magnetic field having a first frequency and a component in a second direction, the second direction being orthogonal to the first direction. The demodulator is configured to demodulate an output signal having the first frequency and outputted from the magnetic field detection element, and detect, on a basis of an amplitude of the output signal, an intensity of a measurement magnetic field to be received by the magnetic field detection element.

Abstract: A magnetic field detection device includes a magnetic field detection element, a modulator, and a demodulator. The magnetic field detection element has a sensitivity axis in a first direction. The modulator is configured to apply, to the magnetic field detection element, a stress oscillating at a first frequency and including a component in a second direction, the second direction being orthogonal to the first direction. The demodulator is configured to demodulate an output signal having the first frequency and outputted from the magnetic field detection element, and detect, on a basis of an amplitude of the output signal, an intensity of a measurement magnetic field to be received by the magnetic field detection element.

Abstract: A capacitive sensor device comprises a first sensor electrode, a second sensor electrode, and a processing system coupled to the first sensor electrode and the second sensor electrode. The processing system is configured to acquire a first capacitive measurement by emitting and receiving a first electrical signal with the first sensor electrode. The processing system is configured to acquire a second capacitive measurement by emitting and receiving a second electrical signal, wherein one of the first and second sensor electrodes performs the emitting and the other of the first and second sensor electrodes performs the receiving, and wherein the first and second capacitive measurements are non-degenerate. The processing system is configured to determine positional information using the first and second capacitive measurements.

Abstract: A gyro sensor includes a plurality of beams connected via a turnaround part. A groove is provided on a main surface of at least one beam of the plurality of beams. Wall thicknesses on the main surface of two sidewalls facing each other of the groove in a direction orthogonal to a longitudinal direction of the beam satisfy 0.9?T1/T2?1.1, where T1 is the wall thickness of one sidewall and T2 is the wall thickness of the other sidewall.

Abstract: A pressure sensor comprises a sensor housing and a sensor header. The sensor housing includes a fastener adapted to be fastened to a pressure measurement target and a housing pathway extending through the fastener and adapted to guide a fluid flowing from the pressure measurement target. The sensor header includes a port pressed in and fixed to the housing pathway, a header pathway extending through the port and adapted to guide the fluid flowing from the housing pathway, and a diaphragm positioned at an end portion of the header pathway.

Abstract: A microelectromechanical component including, vertically at a distance from one another, a substrate device, a first, a second, and a third functional layer, a vertical stop being formed between the second and third functional layer, the vertical stop having a stop area on a surface of the second functional layer facing the third functional layer, wherein the second functional layer is connected to the first functional layer in a connecting area allocated to the stop area.

Abstract: Interdigitated dielectrostrictive sensors are employed to measure shear stress, and for obtaining strain-dielectric and stress-dielectric coefficients to monitor a process, and examine quality of dielectric materials, including but not limited to polymer, composite, grease, food, biofluids and etc. Each dielectrostrictive sensor includes at least two interdigitated sensors, each having at least two electrodes and a central axis. The central axes are disposed in a common plane and are oriented at different directions.

Abstract: The present invention discloses an MEMS pressure sensing element, including a substrate provided with a groove; a pressure-sensitive film disposed above the substrate, the pressure-sensitive film sealing an opening of the groove to form a sealed cavity; and a movable electrode plate and a fixed electrode plate which are located in the sealed cavity and form a capacitor structure, wherein the fixed electrode plate is fixed on a bottom wall of the groove of the substrate, and the movable electrode plate is suspended above the fixed electrode plate and opposite to the fixed electrode plate; and the pressure-sensitive film is connected to the movable electrode plate so as to drive the movable electrode plate to move under the action of an external pressure.

Abstract: The present invention discloses a differential capacitive MEMS pressure sensor and a manufacturing method thereof. The MEMS pressure sensor includes a sensitive structural layer, which includes a common sensitive part and a common supporting part located on the edge of the common sensitive part, a thickness of the common supporting part being larger than that of the common sensitive part; and the MEMS pressure sensor also includes an upper fixed electrode structural layer and a lower fixed electrode structural layer which are vertically symmetric relative to the sensitive structural layer and used for forming differential capacitors with the common sensitive part. According to the MEMS pressure sensor of the present invention, by the differential capacitor structures, inhibition of chips on common-mode signals is enhanced, and a signal to noise ratio of output signals is improved.

Abstract: A pressure sensor comprising: a solid metal sensor body, having a front region and a base adjoining thereto, which has an outer edge, which can be clamped by means of a fastening device; a recess, which is provided in the front region and is open towards a front side of the front region that faces away from the base; a metal measuring diaphragm, to which a pressure is applied from outside during measurement operation and which can be deformed elastically depending upon the pressure, is arranged on the front side of the sensor body, closes off the recess from the outside, and is spaced apart from the outer edge of the front region; and an electromechanical transducer for detection, by means of measuring the pressure-dependent deformation of the measuring diaphragm, having at least one measuring element, which is electrically insulated from the measuring diaphragm and the sensor body by means of an insulating element.

Abstract: Caging structures are disclosed for caging or otherwise reducing the mechanical shock pulse experienced by MEMS device beam structures during events that may cause mechanical shock to the MEMS device. The caging structures at least partially surround the beam such that they limit the motion of the beam in a direction perpendicular to the beam's longitudinal axis, thereby reducing stress on the beam during a mechanical shock event. The caging structures may be used in combination with mechanical shock-resistant beams.

Abstract: A pressure measuring device comprising a bracket supporting a pressure sensor which defines a first sealed enclosure with a first face of the bracket, with the pressure measuring device comprising a substrate having opposite faces, opposite which a first deformable membrane and a second deformable membrane respectively extend, with the first membrane and the second membrane respectively defining with the substrate a second sealed enclosure and a third sealed membrane, with the pressure sensor comprising a cover in order to define a fourth sealed enclosure connected through a second channel to the first enclosure, with the pressure sensor comprising means for measuring the deformation of the first and the second deformable membranes.

Abstract: The pressure sensor of the invention includes at least one platform, at least one measuring membrane 30, and a transducer, wherein the measuring membrane comprises a semiconductor material, wherein the measuring membrane, enclosing a pressure chamber, is secured on the platform, wherein the measuring membrane is contactable with at least one pressure and is elastically deformable in a pressure-dependent manner, wherein the transducer provides an electrical signal dependent on deformation of the measuring membrane, wherein the platform has a membrane bed, on which the measuring membrane lies in the case of overload, in order to support the measuring membrane, wherein the membrane bed 21 has a glass layer 20, whose surface faces the measuring membrane and forms a wall of the pressure chamber, wherein the surface of the glass layer has a contour, which is suitable for supporting the measuring membrane 30 in the case of overload, characterized in that the contour of the membrane bed 21 is obtainable by a sagging

Abstract: Systems and methods for sensing pressure, and protecting a sensor within a sensor assembly. A sensor assembly may comprise a sensor having at least one pressure input port; a first housing configured to encapsulate the sensor; a second housing configured to attach to the first housing to encapsulate the sensor; a first O-ring located between the first housing and the sensor; a second O-ring located between the second housing and the sensor; and a printed circuit board configured to receive detected pressure information from the sensor.

Abstract: A pressure sensor die assembly for a differential pressure sensor comprises a base substrate including a first overpressure stop structure on a first surface, and a diaphragm structure coupled to the first surface. The diaphragm structure comprises a first side with a cavity section that includes a first cavity and a second cavity surrounding the first cavity, and a second side opposite from the first side. A pressure sensing diaphragm portion is defined by the first cavity and is located over the first overpressure stop structure. An overpressure diaphragm portion is defined by the second cavity. A top cap coupled to the second side of the diaphragm structure includes a second overpressure stop structure. The overpressure stop structures are each sized to support substantially all of a strained area of the pressure sensing diaphragm portion at an increasing overpressure on the first or second sides of the diaphragm structure.

Abstract: Shock-resistant MEMS structures are disclosed. In one implementation, a motion control flexure for a MEMS device includes: a rod including a first and second end, wherein the rod is tapered along its length such that it is widest at its center and thinnest at its ends; a first hinge directly coupled to the first end of the rod; and a second hinge directly coupled to the second of the rod. In another implementation, a conductive cantilever for a MEMS device includes: a curved center portion includes a first and second end, wherein the center portion has a point of inflection; a first root coupled to the first end of the center portion; and a second root coupled to the second end of the center portion. In yet another implementation, a shock stop for a MEMS device is described.

Abstract: A pressure difference sensor, comprising a pressure difference measuring cell having a measuring membrane, two platforms, between which the measuring membrane is arranged, and a transducer, as well as an elastic clamping apparatus, which has two clamping areas, each of which acts on a respective rear side of the platform facing away from the measuring membrane. The clamping apparatus has at least one elastic element, via which the clamping areas are mechanically coupled, in order to clamp the pressure difference measuring cell with an axial clamping force. The clamping areas are rigid, wherein the clamping apparatus comprises a clamp with two clamping bodies, each of which has one of the clamping areas. At least one of the clamping bodies has an elastic element, the clamping bodies are connected with one another under stress, in order to exert a clamping force on the pressure difference measuring cell, wherein the two clamping bodies have a central, form retaining section, which includes the clamping areas.

Abstract: A stent including a wire tube and at least one pressure sensor in electrical contact with the wire tube. The pressure sensor includes a diaphragm in communication with a reservoir of liquid, a channel in fluid communication with the reservoir of liquid, and at least one pair of electrodes disposed on opposite sides of the channel, wherein deflection of the diaphragm causes fluid to move from the reservoir into the channel.

Abstract: Transducer assemblies may include a sensor and a housing including a pass-through portion comprising at least one aperture in a portion of the housing extending along a longitudinal axis of the housing and the sensor. Methods of forming transducer assemblies may include welding a first housing section of the transducer assembly to a second housing portion of the transducer assembly and forming at least one aperture in the first housing section extending along a longitudinal axis of the transducer assembly, along a chamber for holding a sensor, and through the weld.

Abstract: In accordance with one embodiment, a single chip combination inertial and pressure sensor device includes a substrate, an inertial sensor including a movable sensing structure movably supported above the substrate, and a first fixed electrode positioned adjacent to the movable sensing structure, and a pressure sensor including a gap formed in the sensor at a location directly above the movable sensing structure, and a flexible membrane formed in a cap layer of the device, the flexible membrane defining a boundary of the gap and configured to flex toward and away from the gap in response to a variation in pressure above the flexible membrane.

Abstract: A system for monitoring a component is provided. The system includes an electrical field scanner for analyzing an electrical field across a reference zone, and a processor in operable communication with the electrical field scanner. The reference zone may include a plurality of fiducials configured on the component to influence the electrical field. The processor may be operable for measuring an electrical field value along a mutually-orthogonal X-axis and Y-axis, assembling a zone profile including a data point set according to the measured electrical field value. Methods of using the system are also provided.

Abstract: A method for manufacture of a pressure sensing mat comprising the steps of: (a) preparing two conductive layers, each conductive layer comprising an array of conducting strips mounted upon a substrate arranged in a parallel fashion, wherein the conducting strips of the first conductive layer are oriented perpendicularly in relation to the conducting strips of the second conductive layer; (b) for each conductive layer, connecting each of the conducting strips to a communication line; (c) sandwiching a compressible layer between the two conductive layers; and (d) performing a pressure reading standardization test to the mat.

Abstract: A micro-electro-mechanical systems (MEMS) device comprises at least one proof mass configured to have a first voltage and a motor motion in a first horizontal direction. At least one sense plate is separated from the proof mass by a sense gap, with the sense plate having an inner surface facing the proof mass and a second voltage different than the first voltage. A set of stop structures are on the inner surface of the sense plate and are electrically isolated from the sense plate. The stop structures are configured to prevent contact of the inner surface of the sense plate with the proof mass in a vertical direction. The stop structures have substantially the same voltage as that of the proof mass, and are dimensioned to minimize energy exchange upon contact with the proof mass during a shock or acceleration event.

Abstract: A vibration driven power generation element according to the present invention includes: a three dimensionally shaped movable comb tooth electrode comprising a plurality of comb teeth of which interiors are filled with an insulating material, and having an SiO2 layer into which alkali ions are injected provided upon its outer surface; and a fixed type comb tooth electrode provided with a plurality of comb teeth made from Si the interiors of which are doped so as to have low electrical resistance, being arranged with the three dimensionally shaped movable comb tooth electrode opposed thereto and interleaved thereinto.

Abstract: A method for manufacturing a MEMS device includes the following operations. An SOI wafer including a device layer, an insulating layer and a handle layer is provided. The device layer is etched to form a recess and an annular protrusion surrounding the recess. A moving part and a spring of the MEMS device are formed on the recess by etching the device layer, the insulating layer and the handle layer. An anchor of the MEMS device is formed at the annular protrusion by etching the device layer, the insulating layer and the handle layer. The moving part and the anchor are connected to each other by the spring. The insulating layer is disposed between a first conductive portion and a second conductive portion of the moving part. The insulating layer is disposed between a first conductive portion and a second conductive portion of the anchor.

Abstract: An acceleration sensor achieving improvement of sensitivity and comprehensive miniaturization as a device includes a first sensor. The first sensor is furnished with an electrostatic capacitor that is configured such that a first fixed electrode, a second fixed electrode and a movable electrode are intensively arranged in a row. In the electrostatic capacitor, the first fixed electrode, the second fixed electrode and the movable electrode are arranged adjoining one another in acceleration detection direction (y-axis direction) at a position corresponding to the center of a weight in a plane view of a substrate. At one of longitudinal-side's ends of each electrode (one of ends in x-axis direction), connectors are provided so as to connect the first fixed electrode and the second fixed electrode to the substrate by connectors.

Abstract: A capacitance type sensor includes: a dielectric layer made of a polymer; an elongated front-side electrode placed on a front side of the dielectric layer; an elongated back-side electrode placed on a back side of the dielectric layer; a front-side wiring connected to the front-side electrode; a back-side wiring connected to the back-side electrode; and a plurality of detection portions formed between the front-side electrode and the back-side electrode. Each of the front-side electrode and the back-side electrode has an elongated electrode body containing a binder and a conductive material, and an extended wiring portion extending in a longitudinal direction of the electrode body and having lower volume resistivity than the electrode body, and the front-side wiring and the back-side wiring have lower volume resistivity than the electrode body.

Abstract: An arrangement for controlling a plasma processing system is provided. The arrangement includes an RF sensing mechanism for obtaining an RF voltage signal. The arrangement also includes a high impedance arrangement coupled to the RF sensing mechanism to facilitate acquisition of the signal while reducing perturbation of RF power driving a plasma in the plasma processing system. The arrangement further includes a signal processing arrangement configured for receiving the signal, processing the signal in a digital domain to obtain peak voltage information for a fundamental frequency and a broadband frequency of the signal, deriving wafer bias information from the peak voltage information, and applying signal to a transfer function to obtain a transfer function output. The arrangement moreover includes an ESC power supply subsystem configured to receive the transfer function output as a feedback signal to control the plasma processing system.

Abstract: A variable capacitor device is disclosed in which the capacitive tuning ratio and quality factor are increased to very high levels, and in which the capacitance value of the device is tuned and held to a desired value with a high level of accuracy and precision using a laser micromachining tuning process on suitably designed and fabricated capacitor devices. The tuning of the variable capacitor devices can be performed open-loop or closed-loop, depending on the precision of the eventual capacitor value needed or desired. Furthermore, the tuning to a pre-determined value can be performed before the variable capacitor device is connected to a circuit, or alternatively, the tuning to a desired value can be performed after the variable capacitor device has been connected into a circuit.

Abstract: A sensor assembly includes a housing assembly, an electrode arrangement and a diaphragm having a fixed portion secured to the housing assembly and an active portion movable relative to the electrode arrangement in response to a differential pressure applied to opposite sides of the diaphragm. The fixed portion of the diaphragm is secured at one or more locations relative to at least a portion of the housing assembly; and at least one groove is formed in the fixed portion of the diaphragm between the locations at which the diaphragm is fixed relative to the housing assembly and the active portion so as to relieve any stress on the active portion of the diaphragm. A method of making the sensor assembly is also disclosed.

Abstract: An integrated circuit metal oxide metal (MOM) variable capacitor includes a first plate; one or more pairs of second plates positioned on both sides of the first plate; one or more pairs of control plates positioned on both sides of the first plate and positioned between the pairs of second plates; and a switch coupled to each control plate and a fixed potential.

Abstract: A novel semiconductor variable capacitor is presented. The semiconductor structure is simple and is based on a semiconductor variable MOS capacitor structure suitable for integrated circuits, which has at least three terminals, one of which is used to modulate the equivalent capacitor area of the MOS structure by increasing or decreasing its DC voltage with respect to another terminal of the device, in order to change the capacitance over a wide ranges of values. Furthermore, the present invention decouples the AC signal and the DC control voltage avoiding distortion and increasing the performance of the device, such as its control characteristic. The present invention is simple and only slightly dependent on the variations due to the fabrication process. It exhibits a high value of capacitance density and, if opportunely implemented, shows a linear dependence of the capacitance value with respect to the voltage of its control terminal.

Abstract: An embodiment of a tunable capacitor can include a plurality of capacitors connected in series where at least two capacitors of the plurality of capacitors share a common electrode where the at least two capacitors are in lateral proximity and a bias that is capable of being applied to the at least two capacitors whereby the at least two capacitors vibrate in opposite phase to each other when the bias and an RF signal is applied to the at least two capacitors.

Abstract: A construction system for a capacitive sensor comprises a source electrode (210), a screening element (220) with partition (221) which forms a first and a second screened chamber (220.a, 220.b), a field sensor (230), a circuit (250), a spacing member (260) with a through-duct, and a screw (270). The partition (221) is provided with a hole (224) and said spacing member (260) is positioned inside the first chamber (220.a) with the axis (260.y) of the duct arranged coaxial with the axis (224-y) of said hole (224). The same spacing member (260) is positioned between the proximal face (223) of the partition (221) and the distal face (232) of the field sensor (230) and said field sensor (230) is provided with a threaded hole (233). The head (271) of the screw (270) is arranged inside the second chamber (220.

Abstract: Embodiments of a method include forming a metal-insulator-metal (MIM) capacitor including a first electrode and a second electrode and an insulator layer between the first and second electrodes, the MIM capacitor also including a reactive layer; and altering the reactive layer to change a capacitive value of the MIM capacitor.

Abstract: A MEMS device of an aspect of the present invention including a MEMS element includes a first lower electrode provided on a substrate, a first insulator which is provided on the upper surface of the first lower electrode, and has a first thickness, and a movable first upper electrode supported by an anchor in midair above the first lower electrode, and a capacitance element includes a second lower electrode provided on the substrate, a second insulator which is provided on the upper surface of the second lower electrode, and has a second thickness, and a second upper electrode provided on the second insulator, wherein the second thickness is less than the first thickness.

Abstract: A mechanical drive system for a vacuum capacitor is provided and includes a drive screw and a nut, wherein the nut is arranged in a housing of the vacuum capacitor, wherein the drive screw is screwed through the nut, wherein a first electrode is arranged on one side of the drive screw, wherein, by a rotation of the drive screw, the first electrode is movable relative to a second electrode, and wherein the nut is at least partially manufactured out of a plastic material.

Abstract: A capacitive switch for microelectromechanical systems (MEMS) comprises a topmost metal plate which extends across a bridge structure formed by a polymer layer. The polymer layer comprises poly-monochoro-para-xylene (parylene-C). The space below the polymer layer contains the second plate on a substrate. Using parylene as the primary bridge material makes the bridge of the MEMS device very flexible and requires a relatively low actuation voltage to pull the bridge down and lower power is required to control the MEMS device.

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 tunable capacitor using an electrowetting phenomenon includes a first electrode; a second electrode which is spaced apart from the first electrode and faces the first electrode; a fluidic channel which is disposed between the first electrode and the second electrode; a first insulating layer which is disposed between the first electrode and the fluidic channel; and a conductive fluid which is disposed in the fluidic channel and moves along the fluidic channel when a direct current (DC) potential difference occurs between the first and second electrodes. Accordingly, it is possible to fabricate the tunable capacitor with the simplified fabrication process, good reliability and durability, and no restriction on the tuning range.

Abstract: An array variable capacitor apparatus includes a line unit including a ground line and a signal line which operates as a lower electrode; and a plurality of plates which are engaged with the line unit to generate capacitance and which operate as upper electrodes, the plurality of plates being arranged in an array pattern and having different degrees of stiffness.

Abstract: A capacitance arrangement comprising at least one parallel-plate capacitor comprising a first electrode means, a dielectric layer and a second electrode means partly overlapping each other. A misalignment limit is given. Said first electrode means comprises a first and a second electrode arranged symmetrically with respect to a longitudinal axis, said first and second electrodes have a respective first edge, which face each other, are linear and parallel such that a gap is defined there between. Said second electrode means comprises a third electrode with a first section and a second section disposed on opposite sides of said gap interconnected by means of an intermediate section, which is delimited by a function depending on a first parameter and a second parameter. One of said two parameters is adapted to be selected hence allowing calculation of the other parameter to determine the shape and size of the second electrode means.

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: In an embodiment of the present invention is provided a varactor comprising a substrate, a bottom electrode positioned on a surface of the substrate, a tunable dielectric material positioned adjacent to and extending over the bottom electrode forming a step and in contact with a top electrode, and an interconnect layer in contact with the bottom electrode, the tunable dielectric and the top electrode.

Abstract: One inventive aspect relates a variable capacitor comprising first and second electrically conductive electrodes, arranged above a support structure and spaced apart from each other and defining the capacitance of the capacitor. At least one of the electrodes comprises at least one bendable portion. The bendable portion(s) are actuated by a DC voltage difference which is applied over the electrodes to vary the capacitance. In preferred embodiments, the support structure comprises a layer of higher permittivity than the atmosphere surrounding the electrodes and the electrodes configure as an interdigitated structure upon actuation. Also disclosed is a 2-mask process for producing such capacitors.

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: 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: 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-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.