Abstract: An accelerometer includes an inertial body; a magnetized fluid holding the inertial body in suspension; and a plurality of capacitive elements, each forming a capacitor with the inertial body. A displacement of the inertial body produces a change of capacitance of the capacitive elements that is indicative of acceleration. The capacitive elements include at least two capacitive elements per side of the accelerometer. A housing encloses the inertial body and the magnetized fluid, and the plurality of capacitive elements are mounted on the housing. The housing can be cylindrical shaped, rectangular shaped and tetrahedral-shaped. The inertial body can include a disk-shaped magnet, an annular-shaped magnet, or be non-magnetic, or be weakly magnetic. The acceleration can be linear acceleration, angular acceleration, or three components of angular acceleration and three components of linear acceleration. A plurality of magnets magnetize the magnetic fluid.

Abstract: A fingerprint sensing system includes an image sensor, a rate sensor and a sensor circuit. The image sensor includes a linear array of capacitive sensors for capacitive sensing of ridge peaks and ridge valleys of a fingerprint on a swiped finger. The rate sensor senses the speed of the finger as it is swiped across the image sensor. The sensor circuit supplies image drive signals to the image sensor and detects image signals in response to the drive signals. The sensor circuit supplies rate drive signals to the rate sensor and detects rate signals in response to the rate drive signals. The sensor circuit further coordinates the image signals and the rate signals to provide a fingerprint image. The image sensor may be configured as an image pickup plate and multiple image drive plates formed on a substrate, such as a flexible printed circuit board or other flexible substrate which may conform to the shape of the finger.

Abstract: An apparatus and method for force sensing device having a pendulous mechanism proof mass formed in a silicon semiconductor substrate and structured for rotation about an intermediate rotational axis, the proof mass being substantially rectangular in shape with opposing first and second lateral peripheral edges and opposing first and second endwise peripheral edges. A plurality of capacitor comb teeth are formed symmetrically along the opposing first and second endwise peripheral proof mass edges and along the opposing first and second lateral peripheral proof mass edges adjacent to the first and second endwise peripheral edges, and one or more mass reduction apertures are formed in an interior portion of the proof mass on one side of the intermediate hinge axis.

Abstract: An accelerometer device comprises a dielectric seismic mass separated by a gap from an underlying comb-shaped planar capacitor. The principle for measuring acceleration detecting capacitance change according to movement of the dielectric mass in the fringe electrical field. This measuring principle is verified by FEM simulation. The simple structure of the accelerometer device allows the polymer Parylene to be used as the proof mass, greatly simplifying the technology by requiring only surface micromachining. Prototype accelerometers are fabricated and calibrated with the aid of off-chip capacitive readout IC.

Abstract: Micromachined structures, such as fixed drive or sensing fingers of an inertial sensor, are anchored to a substrate using multiple anchors or elongated anchors in order to reduce the bending or twisting of the micromachined structure about the anchor point.

Abstract: A sensor having a seismic mass and having an arrangement for detecting the deflection of the mass and converting it into an electrical signal; in at least one operating mode of the sensor, a mechanical stop asymmetrically limiting the deflection of the seismic mass with respect to a vibrational center position. An arrangement for symmetrical limiting of the signal provided on the sensor.

Abstract: A physical quantity sensor is constituted using a plurality of piezoelectric sensors each having first and second semiconductor layers realizing resistances and terminals, and a conductive weight portion in relation to an opening of an insulating film that partially exposes the main surface of a substrate. Both the semiconductor layers are elongated from the periphery of the opening on the insulating film inwardly into the opening so as to three-dimensionally support the conductive weight portion in a floating manner, thus realizing three-dimensional displacement. A capacitance electrode layer is arranged in the bottom of the opening on the main surface of the substrate so as to establish capacitance with the conductive weight portion. The displacement of the conductive weight portion is detected based on resistance variations and capacitance variations. Thus, it is possible to detect physical quantity such as acceleration, vibration, and inclination with a reduced chip size.

Abstract: A capacitance accelerometer includes a housing, and a plate fixed within the housing. A moveable plate is disposed in substantially parallel relation to the fixed plate and is coupled to the housing along at least an edge. The moveable plate and the fixed plate define a distance. The distance varies in response to acceleration forces acting upon the moveable plate, and wherein the moveable plate and the fixed plate generate a charge displacement capacitance signal. A transimpedance amplifier receives the charge displacement capacitance signal and generates a scaled voltage signal therefrom. An acceleration signal is generated from the scaled voltage signal.

Abstract: An accelerometer includes a pair of conductive plates fixedly mounted on a substrate surface, a structure coupled to the substrate surface and suspended above the conductive plates, and at least one protective shield mounted on the substrate surface. The structure includes two regions of differing total moments disposed above a respective conductive plate and separated by a flexure axis about which the structure rotates during an acceleration normal to the substrate, each region having a substantially planar outer surface and an inner surface having a first corrugation formed thereon. For each of the two regions, an inner gap exists between the first corrugation and an opposing conductive plate, and an outer gap exists between the substantially planar outer surface and the opposing conductive plate, the outer gap being larger than the inner gap. The at least one protective shield is placed apart from either of the conductive plates.

Abstract: Oscillators have capacitors, respectively, whose capacitances change according to an external force and generate first oscillating signals according to the capacitances. Each of the capacitors is disposed, for example, between a substrate and a mass body that is movably disposed to face the substrate and oscillates in a direction perpendicular to the substrate. A detecting unit detects a relative difference between the capacitances of the capacitors as a difference between frequencies of the first oscillating signals. An angular speed or acceleration applied in a horizontal direction of the substrate is calculated according to the frequency change detected by the detecting unit. Therefore, a capacitance difference detecting circuit and a MEMS sensor that detect a minute change in the capacitances of the two capacitors caused by the external force are formed.

Abstract: A physical quantity sensor detects a physical quantity. The sensor includes a movable portion having a bottom and a protrusion disposed on the bottom of the movable portion. The protrusion is provided without adding a manufacturing process, so that a manufacturing cost is reduced. Preferably, the protrusion is provided by a remaining portion, which remains without being etched when the movable portion is prepared by etching.

Abstract: In a capacitive physical quantity sensor, a C-V converter converts a variation in a capacitance between a movable electrode and a fixed electrode into a voltage to output the converted voltage in a first operating mode. The C-V converter also outputs a constant voltage in a second operating mode. An amplifier amplifies the converted voltage to output a first voltage, and amplifies the constant voltage to output a second voltage. A first sample and hold circuit operates in the first operating mode to sample and hold the first voltage. A second sample and hold circuit operates in the second operating mode to sample and hold the second voltage. A first differential amplifier obtains a difference voltage between the first voltage held by the first sample and hold circuit and the second voltage held by the second sample and hold circuit.

Abstract: A capacitance type acceleration sensor includes a semiconductor substrate, a weight portion supported with the substrate through a spring portion, a movable electrode integrated with the weight portion, and a fixed electrode cantilevered with the substrate. The movable electrode is displaced along with a facing surface of the movable electrode in accordance with acceleration. The facing surface of the movable electrode faces a facing surface of the fixed electrode so as to provide a capacitor. The capacitance of the capacitor changes in accordance with a displacement of the movable electrode so that an outer circuit detects the acceleration as a capacitance change. Each facing surface of the movable and fixed electrodes has a concavity and convexity portion for increasing the capacitance change.

Abstract: A bridge accelerometer system includes four capacitors, wherein two capacitors are formed on each side of a rigid member. The other two capacitors are similarly constructed, except that the rigid member is replaced by a flexured plate. The construction of the plates with respect to the flexured plate is substantially similar to the configuration formed by the rigid member and the other two capacitors, and the fixed capacitors and rigid plate are isolated from the flexured arrangement. The four capacitors are connected to form a bridge generating a bridge voltage signal as a function of a sine wave from a symbol generator. The bridge voltage signal is amplified and converted to digital word in an A/D converter. The digital word is linearized and filtered in a microprocessor, which also includes a precision clock controlling the symbol generator and a conversion clock controlling the A/D converter.

Abstract: A semiconductor device includes gaps formed in a semiconductor substrate to provide an inner portion movable in x and y directions. Drive electrodes vibrate the inner portion in the x direction, and detection electrodes detect movement in the y direction generated when an angular velocity is applied thereto. Monitor electrodes generate monitor signals for monitoring movement of the inner portion in the x direction. Shield wires are provided between the drive and detection electrodes and the monitor electrodes to suppress capacitive coupling. Dummy electrodes adjacent to the output electrodes and capacitively coupled to the drive electrodes generate a dummy signal. Dummy signal wires are respectively connected to the dummy electrodes and to the circuit substrate. The dummy signal includes an induced component of a periodical signal and is supplied to the circuit substrate to cancel another induced component of the periodical signal in the drive and monitor signals.

Abstract: A fingerprint sensing system includes an image sensor, a rate sensor and a sensor circuit. The image sensor includes a linear array of capacitive sensors for capacitive sensing of ridge peaks and ridge valleys of a fingerprint on a swiped finger. The rate sensor senses the speed of the finger as it is swiped across the image sensor. The sensor circuit supplies image drive signals to the image sensor and detects image signals in response to the drive signals. The sensor circuit supplies rate drive signals to the rate sensor and detects rate signals in response to the rate drive signals. The sensor circuit further coordinates the image signals and the rate signals to provide a fingerprint image. The image sensor may be configured as an image pickup plate and multiple image drive plates formed on a substrate, such as a flexible printed circuit board or other flexible substrate which may conform to the shape of the finger.

Abstract: A piezoelectric vibrator 2 that generates an electric charge according to a stress and a weight 1 provided on the piezoelectric vibrator 2 are included. The piezoelectric vibrator 2 has multiple pairs of sensing electrodes 3a and 3b, and 4a and 4b, and the sensing electrodes 3a and 3b, and 4a and 4b are respectively connected in parallel so that capacitances Cd1 and Cd2 made of the sensing electrodes may be connected in parallel. It is thus possible to double the charge sensitivity with keeping the voltage sensitivity.

Abstract: A process for forming a microelectromechanical system (MEMS) device by a deep reactive ion etching (DRIE) process during which a substrate overlying a cavity is etched to form trenches that breach the cavity to delineate suspended structures. A first general feature of the process is to define suspended structures with a DRIE process, such that the dimensions desired for the suspended structures are obtained. A second general feature is the proper location of specialized features, such as stiction bumps, vulnerable to erosion caused by the DRIE process. Yet another general feature is to control the environment surrounding suspended structures delineated by DRIE in order to obtain their desired dimensions. A significant problem identified and solved by the invention is the propensity for the DRIE process to etch certain suspended features at different rates.

Abstract: A method for designing and optimnizing compliant mechanisms is provided, in addition to bistable compliant mechanism designs. According to the method, a selected compliant structure may be modeled analytically, and the characteristics of the analytical model may be optimized. Multiple recursive optimization algorithms may be used, for example, to determine the general location of a global optimum, and then to determine the values of the analytical model characteristics that obtain the global optimum or a feasible configuration for the selected compliant structure. Geometric characteristics of the selected compliant structure may be derived from the values of the analytical model characteristics. Bistable compliant designs may have a shuttle disposed between a pair of base members. The shuttle (20) may be linked to the base members (22, 24) by a pair of legs (30, 32), via flexural pivots. The base members may have cantilevered mounting beams to create deformable mounts that receive and store potential energy.

Abstract: A high aspect ratio microelectromechanical system device for measuring an applied force, the device being a cellular in-plane accelerometer formed of a base having a substantially planar mounting surface. A pair of substantially rigid fixed electrode structures are formed in a doped silicon mechanism layer, the fixed electrode structures having substantially parallel and mutually opposing pickoff electrode surfaces oriented substantially perpendicular to the planar mounting surface of the base and spaced apart along an input direction parallel with the planar mounting surface of the base, each of the fixed electrode structures being anchored to the mounting surface of the base. A pendulous electrostatic comb is formed in the doped silicon mechanism layer and oriented substantially perpendicular to the planar mounting surface of the base, the electrostatic comb being pendulously suspended from the mounting surface of the base between the fixed electrode structures for motion along the input direction.

Abstract: An acceleration sensor is formed on a top surface of a laminated silicon-on-insulator substrate. The acceleration sensor is composed of first and second capacitors each including a movable electrode that moves according to acceleration imposed thereon. The first and the second capacitors are so made that their capacitances change differently when the same acceleration is imposed and that the capacitance difference represents an amount of acceleration imposed thereon. A third capacitor having an output electrode solidly connected to the base substrate via the insulation layer is also formed on the same silicon-on-insulator substrate. An output representing amount of acceleration is taken out from the output electrode of the third capacitor.

Abstract: A semiconductor mechanical sensor having a new structure in which a S/N ratio is improved. In the central portion of a silicon substrate 1, a recess portion 2 is formed which includes a beam structure. A weight is formed at the tip of the beam, and in the bottom surface of the weight in the bottom surface of the recess portion 2 facing the same, an electrode 5 is formed. An alternating current electric power is applied between the weight portion 4 and the electrode 5 so that static electricity is created and the weight is excited by the static electricity. In an axial direction which is perpendicular to the direction of the excitation of the weight, an electrode 6 is disposed to face one surface of the weight and a wall surface of the substrate which faces the same. A change in a capacitance between the facing electrodes is electrically detected, and therefore, a change in a physical force acting in the same direction is detected.

Abstract: A biometric sensing device includes sensing arrays for sensing a biological surface swiped across the sensing arrays in an arbitrary direction. This device allows for simultaneously sensing different features of a biological surface where the features have the smallest distinguishable features of different size. Using the technique of interleaving partial images, the resolution of the biometric sensing device is increased. Therefore, a small and robust biometric sensing device is provided, which allows for sensing high resolution images.

Abstract: An accelerometer or a seismometer using an in-plane suspension geometry having a suspension plate and at least one fixed capacitive plate. The suspension plate is formed from a single piece and includes an external frame, a pair of flexural elements, and an integrated proof mass between the flexures. The flexural elements allow the proof mass to move in the sensitive direction in the plane of suspension while restricting movement in all off-axis directions. Off-axis motion of the proof mass is minimized by the use of intermediate frames disbursed within and between the flexural elements. Intermediate frames can include motion stops to prevent further relative motion during overload conditions. The device can also include a dampening structure, such as a spring or gas structure that includes a trapezoidal piston and corresponding cylinder, to provide damping during non-powered states.

Abstract: A system including a user input device for controlling a position of medical equipment is described. In an example embodiment, the user input device is configured to be coupled to the medical equipment and is responsive to an operator input representation of a desired movement of the equipment. A processor determines a direction in which the operator desires the equipment to move based on a device output.

Abstract: An apparatus and method for sensing accelerations and other forces. The apparatus having a capacitance pick-off force sensor having a proof mass that is suspended relative to a relatively stationary frame by a plurality of serpentine suspension members having internal caging. The device provides easily implemented fabrication modification for trading-off between input range and pick-off sensitivity by altering etching periods of the serpentine suspension members. The input range and pick-off sensitivity can be traded-off by enlarging or reducing the quantity of elongated flexure fingers forming the serpentine suspension member. Different ones of the elongated flexure fingers are optionally formed with different thicknesses, whereby the serpentine suspension member exhibits a spring rate that progressively increases as it is compressed by in-plane motion of the proof mass relative to the relatively stationary frame.

Abstract: A Micro Electro-Mechanical System (MEMS) acceleration sensing device, formed of a an elongated sensing element of substantially uniform thickness suspended for motion relative to a rotational axis offset between first and second ends thereof such that a first portion of the sensing element between the rotational axis and the first end is longer than a shorter second portion between the rotational axis and the second end; a stationary silicon substrate spaced away from the sensing element; a capacitor formed by a surface of the substrate and each of the first and second portions of the sensing element; and a valley formed in the substrate surface opposite from the first longer portion of the sensing element and spaced away from the rotational axis a distance substantially the same as the distance between the rotational axis and the second end of the sensing element.

Abstract: An apparatus and method for sensing accelerations and other forces. The apparatus having a capacitance pick-off force sensor having a proof mass that is suspended relative to a relatively stationary frame by a plurality of serpentine suspension members having internal caging. The device provides easily implemented fabrication modification for trading-off between input range and pick-off sensitivity by altering etching periods of the serpentine suspension members. The input range and pick-off sensitivity can be traded-off by enlarging or reducing the quantity of elongated flexure fingers forming the serpentine suspension member. Different ones of the elongated flexure fingers are optionally formed with different thicknesses, whereby the serpentine suspension member exhibits a spring rate that progressively increases as it is compressed by in-plane motion of the proof mass relative to the relatively stationary frame.

Abstract: There is provided a compact, high-sensitivity acceleration sensor. The acceleration sensor includes a weight 8, a pedestal 9 arranged around the periphery of the weight 8, a support frame 3 formed to have a width narrower than the width of the pedestal 9 all around its perimeter, a mass 2 attached to the weight 8 to retain the weight 8 inside the support frame 3, beams 4 connecting the support frame 3 and the mass 2 and overlapping the pedestal 9 near their ends on the side of the support frame 3, and a peripheral interlayer 12 arranged between the support frame 3 and the pedestal 9 to create a predetermined clearance between the pedestal 9 and the parts of the beams 4 that overlap the pedestal 9.

Abstract: In a semiconductor dynamic quantity sensor, a mass serving as a weight portion for detecting application of a dynamic quantity is divided into three masses (301, 302, 303) in series. The masses (301, 302, 303) thus divided are connected to one another by connecting beams (CB1, CB2, CB3, CB4). The masses (301, 302, 303) located at both the end portions are supported through beams (B1, B2, B3, B4) by a semiconductor substrate (1) so as to be allowed to be displaced in the direction orthogonal to the connection direction of the masses. The center mass (302) connected to the masses (301, 302, 303) through the connecting beams (CB1, CB2, CB3, CB4) is allowed to be displaced only in the connecting direction of the masses by the connecting beams (CB1, CB2, CB3, CB4).

Abstract: In a semiconductor acceleration sensor (S1), above one side of a first silicon substrate (10) made of a semiconductor and serving as a fixed electrode (11), a moving electrode (20) made of a semiconductor and displaceable in the thickness direction of the first silicon substrate (10) is disposed apart from and facing the first silicon substrate (10). An applied acceleration is detected on the basis of capacitance changes between the moving electrode (20) and the face of the first silicon substrate (10) accompanying displacement of the moving electrode (20). A space and an electrically insulative insulating layer (13) having a relative permittivity larger than that of air are interposed between the moving electrode (20) and the face of the first silicon substrate (10), side by side in the direction in which the moving electrode (20) and the first silicon substrate (10) are apart.

Abstract: A capacitance type acceleration sensor includes a semiconductor substrate, a weight portion supported with the substrate through a spring portion, a movable electrode integrated with the weight portion, and a fixed electrode cantilevered with the substrate. The movable electrode is displaced along with a facing surface of the movable electrode in accordance with acceleration. The facing surface of the movable electrode faces a facing surface of the fixed electrode so as to provide a capacitor. The capacitance of the capacitor changes in accordance with a displacement of the movable electrode so that an outer circuit detects the acceleration as a capacitance change. Each facing surface of the movable and fixed electrodes has a concavity and convexity portion for increasing the capacitance change.

Abstract: A plane vibrator of an angular velocity sensor and a movable member of an acceleration sensor are provided in a spaced floating state on the same substrate. A lid is formed so as to cover and be spaced from the upper side of the plane vibrator and the movable member. A space defined by the substrate and the lid is sectioned into a angular velocity sensor space and an acceleration sensor space by use of a sectioning wall. The angular velocity sensor space is hermetically sealed to be in the vacuum state. The acceleration sensor space is hermetically sealed to be under atmospheric pressure. The plane vibrator is vibrated at a high frequency and a large amplitude so that the angular velocity detection sensitivity is enhanced. The movable member, even if vibration of the plane vibrator is transmitted thereto, is prevented from vibrating at a high frequency and a large amplitude, due to the damping effect of air. Thus, the acceleration detection sensitivity is enhanced.

Abstract: Disclosed is a capacitance accelerometer comprising a fixed electrode, a movable electrode and support beams. The fixed electrode has rectangular fixed electrode plates arranged parallel with a top surface of an insulation board. The fixed electrode plates are placed one above another via posts, and arranged on an electrode-fixing section of the insulation board. The movable electrode has rectangular movable electrode plates alternating with the fixed electrode plates. The movable electrode plates are placed one above another via connector posts placed within guide holes perforated through the fixed electrode plates. The support beams connect the movable electrode with beam-fixing sections to elastically support the movable electrode. The capacitance z-axis accelerometer can be integrated together with x- and y-axis accelerometers into a single chip, maximize the change of capacitance to achieve excellent acceleration sensitivity, and utilize an amplifier and a filter of low cost.

Abstract: A moving member having a plurality of moving electrodes is supported by support members at both ends thereof on a substrate surface in such a way that it can be subjected to displacement in a two-dimensional plane. A plurality of fixed electrodes are arranged to face the plurality of moving electrodes respectively, thus forming different facing areas therebetween when an input acceleration is zero. The facing areas formed between pairs of the electrodes facing each other are varied in response to the displacement of the moving member, whereby a capacitance caused by one pair of the electrodes whose facing area is relatively small is used to detect a relatively small input acceleration, and a capacitance caused by the other pair of the electrodes whose facing area is relatively large is used to detect a relatively large input acceleration.

Abstract: An apparatus in one example includes a compliant component for supporting an electrical interface component that serves to electrically and mechanically couple a die with a separate layer. In one example, the compliant component, upon relative movement between the die and the separate layer, serves to promote a decrease in stress in one or more of the die and the separate layer. The apparatus in another example includes a compliant component for supporting an electrical interface component that serves to create an electrical connection between a die and a separate layer. The compliant component, upon relative movement between the die and the separate layer, serves to promote maintenance of the electrical connection.

Abstract: A micro-electromechanical (MEM) device has a folded tether spring in which each fold of the spring is surrounded by a rigidly fixed inner structure and outer structure. The fixed inner structure increases restoring force of the spring. The rigidly fixed inner and outer structures each have a major surface that include a plurality of notches of fixed width relative to a distance between the major surface and the spring. Additionally in one form extensions from the major surface of the rigidly fixed inner and outer structures are provided at distal ends thereof to make initial contact with the spring. The notches of the MEM device both reduce surface area contact with the spring and wick moisture away from the spring to minimize stiction.

Abstract: An inertial detecting device for detecting a change in capacitance of a sensor element caused by inertial force includes a displaceable unit. The displaceable unit includes a movable mass member which is displaceable in the direction of an inertial force and is supported in a space by a pair of beams fixed on the substrate. At least one pair of detection units for detecting the displacement of the displaceable unit are provided on the substrate. The detection unit includes a drive unit and a pair of sensing electrodes which are disposed opposite to the displaceable unit. Any gap can be freely set between the sensing electrode and the movable mass member, thereby changing the sensitivity of the detecting device in a wide range.

Abstract: A semiconductor dynamic quantity sensor includes a semiconductor substrate that includes a movable electrode, a pair of first fixed electrodes, and a pair of second fixed electrodes. The first and second pairs of first detection capacitances and the first and second pairs of second detection capacitances are formed by the electrodes. The dynamic quantity related to the force applied to the sensor is measured on the basis of the sum of the differential output between the first pair of the first detection capacitances, the differential output between the second pair of the first detection capacitances, the differential output between the first pair of the second detection capacitances, and the differential output between the second pair of the second detection capacitances, when the movable electrode moves along the first direction or the second direction under the force. The sum includes a relatively small amount of noises.

Abstract: An acceleration sensor includes an acceleration sensor element and a frame portion surrounding the element. The sensor element and the frame portion are located on a major surface of a substrate. An intermediate layer is formed on the frame portion. A cap portion is bonded to the intermediate layer, thereby sealing-off the acceleration sensor element. Grooves in the form of a frame are provided in the frame portion and the intermediate layer, respectively, and located at positions generally identical to each other with regard to the major surface direction of the substrate.

Abstract: A sensor element includes a pair of differential capacitors having capacitances C1 and C2 causing a complementary capacitance change in response to an applied acceleration. An additional capacitor is connected to either capacitor to generate a capacitance difference between the capacitance C1 and the composite capacitance C2+C3. This enables to adjust an input LPFout of a correcting circuit correcting the offset level of the sensor output Gout in such a manner that a correction amount in the correcting circuit becomes large and accordingly deviates sufficiently from a reference level Vref. In case of failure in which the input of the correcting circuit is fixed to the reference level Vref, the sensor output Gout surely deviates from the reference level Vref by an amount equivalent to the correction in the correcting circuit.

Abstract: In a capacitive type dynamic quantity sensor, a width of a beam in a beam portion extending in a direction that is perpendicular to a predetermined deformation direction and a gap disposed between a movable electrode and the fixed electrode in the predetermined deformation direction are approximately identical. Accordingly, manufacturing error is prevented from affecting the sensitivity of the capacitive type dynamic quantity sensor. For example, a manufacturing tolerance error of ±2.5% is allowed as a result of designing the width of the beam and the gap to be identical in length.

Abstract: By applying a first value of voltage to a first side of a MEMS gyroscope and applying a second value of voltage to a second side of the MEMS gyroscope, the start time of the MEMS gyroscope may be improved. The first and second value of voltage may be provided by a bias power source, such as a battery or a super capacitor. The first value of voltage may be substantially equal in magnitude to and opposite in polarity to the second value of voltage. The bias power source may also be applied to drive electronics connected to the MEMS gyroscope. The bias power source may prevent amplifiers within the drive electronics from saturating during the start time.

Abstract: A multi-axis solid state accelerometer is made of electricity conductive material and is made by way of micro-machining. The main structure includes at least one proof mass connected to an anchor by several sensing beams and two boards are located on two sides of the main structure and fixed to the anchor. The sensing beams make the proof mass movable in parallel to or perpendicular to the boards. The surfaces of the proof mass include several grooves, which are parallel to the first axis and the second axis, and an area that has no grooves. Each board that face the grooves include two sets of electrodes and each of which includes several elongate electrodes located corresponding to the grooves. The two sets of elongate electrodes are located interposed each other. The board facing the area having no grooves has electrodes. The electrodes and the surfaces of the proof mass form detection capacitors for each axis.

Abstract: A semiconductor dynamic quantity sensor has a support substrate with a rectangular opening portion, and a movable electrode and fixed electrodes are respectively supported by the support substrate through supporting portions to face the opening portion. The supporting portions supporting the movable electrode are arranged in a direction approximately the same as that in which the supporting portions supporting the fixed electrodes are arranged.

Abstract: An accelerometer includes a capacitive sensing device and circuitry. The capacitive sensing device has electrode structures spaced by a gap for relative movement in response to a force applied to the capacitive sensing device to produce a displacement of the electrode structures. A liquid is disposed in the gap between the electrode structures. The circuitry is coupled to the capacitive sensing device for determining from the displacement an electric signal indicative of acceleration of the applied force.

Abstract: A microfabricated device having a high vertical aspect ratio and electrical isolation between a structure region and a circuit region. The device may be fabricated on a single substrate and may include electrical interconnections between the structure region and the circuit region. The device includes a substrate and an isolation trench surrounding a structure region in the substrate. The isolation trench includes a lining of a dielectric insulative material. A plurality of microstructure elements are located in the structure region and are laterally anchored to the isolation trench.

Abstract: An acceleration sensor includes first and second fixed electrodes on a substrate, and a movable electrode located above the first and second fixed electrodes, with respect to the substrate, and facing them. The movable electrode is elastically supported on the substrate by a first elastic supporting body and is movable. A mass, which is elastically supported on the substrate by a second elastic supporting body, moves in response to an acceleration in a direction perpendicular to the substrate. A linking portion links the movable electrode and the mass at a position spaced from an axis of movement of the movable electrode by a distance. Acceleration is measured based on changes in a first capacitance between the first fixed electrode and the movable electrode and a second capacitance between the second fixed electrode and the movable electrode. Thus, a highly impact resistant and highly reliable acceleration sensor is obtained.

Abstract: A method for manufacturing a semiconductor device having a movable unit includes a step of forming an SOI substrate that includes a semiconductor substrate, an insulating layer, and a semiconductor layer such that the insulating layer is located between the semiconductor layer and the semiconductor substrate. The method further includes a step of dry etching the semiconductor layer to form a trench with a charge prevented from building up on a surface of the insulating layer that is exposed at a bottom of the trench during the dry etching. The method further includes a step of dry etching a sidewall defining the trench at a portion adjacent to the bottom of the trench to form the movable unit. The later dry etching is performed with a charge building up on the surface of the insulating layer such that etching ions strike to etch the portion of the sidewall.

Abstract: An apparatus is provided for concurrently detecting a plurality of physical quantities to be detected. The apparatus comprises plural sensing units, plural processors, and controller. The sensing units are formed on the same substrate to form a single sensor. Each sensing unit senses each physical quantity to output a voltage signal changing depending on each physical quantity sensed. Each of the processors samples and holds, at a predetermined frequency, the voltage signal outputted by each of the sensing units. Hence sampled and held voltage signals are produced and outputted from the apparatus as information indicative of the plurality of physical quantities. In the sampling and holding processing, a controller controls the plural processors so that the processors perform sampling operations at predetermined different phases shifted from each other during an interval defined by the predetermined frequency.