A vibration sensor having a moveable mass adapted to move in response to vibrations or accelerations. The sensor includes a damping arrangement that includes a damping fluid or gel. The moveable mass is arranged to interact directly or indirectly with the damping fluid or gel in order to reduce a mechanical resonance peak of the vibration sensor. The damping fluid or gel has a viscosity between 1000 cP and 100000 Cp and damping properties that are substantially stable over time.

A capacitive accelerometer comprises: a substantially planar proof mass mounted to a fixed substrate by flexible support legs so as to be linearly moveable in an in-plane sensing direction. The proof mass comprises first and second sets of moveable capacitive electrode fingers. First and second sets of fixed capacitive electrode fingers interdigitates with the first and second sets of moveable electrode fingers respectively. A set of moveable damping fingers extend from the proof mass substantially perpendicular to the sensing direction, laterally spaced in the sensing direction. A set of fixed damping fingers mounted to the fixed substrate interdigitates with the set of moveable damping fingers and comprises an electrical connection to the proof mass so that the interdigitated damping fingers are electrically common. The damping fingers are mounted in a gaseous medium that provides a damping effect.

There is provided a resonant sensor comprising: a substrate; a proof mass suspended from the substrate by one or more flexures to allow the proof mass to move relative to the frame along a sensitive axis; a first and a second resonant element connected between the frame and the proof mass; wherein the proof mass is positioned between the first and the second resonant element along the sensitive axis, and wherein the first and the second resonant elements have a substantially identical structure to one another; and drive and sensing circuitry comprising: a first electrode assembly coupled to first drive circuitry configured to drive the first resonant element in a first mode; a second electrode assembly coupled to second drive circuitry configured to drive the second resonant element in a second mode, different to the first mode; and a sensing circuit configured to determine a measure of acceleration.

A micromechanical structure for an acceleration sensor includes a movable seismic mass including electrodes, the seismic mass being attached to a substrate with the aid of an attachment element; first fixed counter electrodes attached to a first carrier plate; and second fixed counter electrodes attached to a second carrier plate, where the counter electrodes, together with the electrodes, are situated nested in one another in a sensing plane of the micromechanical structure, and where the carrier plates are situated nested in one another in a plane below the sensing plane, each being attached to a central area of the substrate with the aid of an attachment element.

There is provided a resonant sensor comprising: a substrate; a proof mass suspended from the substrate to allow for relative movement between the proof mass and the substrate along at least one sensitive axis; at least one resonant element coupled to the proof mass; an electrode assembly adjacent to the at least one resonant element; drive and sense circuitry connected to the electrode assembly configured to drive the electrode assembly to cause the at least one resonant element to resonate, wherein a measure of acceleration of the proof mass can be determined from changes in the resonant behavior of the at least one resonant element; at least one substrate electrode on the substrate, adjacent to the proof mass; and electric circuitry connected to the substrate electrode configured to apply a voltage to the substrate electrode providing an electrostatic force on the proof mass. The substrate electrode may be used to provide a number of different functions.

A vibration sensor having a moveable mass being suspended in a suspension member and being adapted to move in response to vibrations or accelerations. The moveable mass and the suspension member move together as a single element. The vibration sensor includes a damping arrangement having a damping fluid or gel. The moveable mass is arranged to interact directly or indirectly with the damping fluid or gel in order to reduce a mechanical resonance peak of the vibration sensor. The damping fluid or gel has a viscosity between 1000 cP and 100000 cP, is kept in position by capillary forces only, and is stable over time without tending to evaporate.

The disclosure relates to a microelectromechanical device where the device structure includes a rotating mass structure and a linear mass structure. The rotating mass structure is formed of two rotating mass parts elastically coupled to the support through one or more springs that enable rotary motion of each of the rotating mass parts about respective rotary axes that extend parallel to each other along a first in-plane direction (IP1). The linear mass structure includes at least one elongate rigid body that extends in a second in-plane direction (IP2). One end of the linear mass structure is coupled to the first rotating mass part and the other end of the linear mass structure is coupled to the second rotating mass part such that rotary motions of the first and second masses result into linear motion of the linear mass structure in the out-of-plane direction (OP).

The disclosure discloses an acceleration sensor, where the acceleration sensor comprises: a housing, and a mass block in the housing and connected with the housing via at least two hanging beams, where an auxiliary buffer component is further provided between the mass block and a bottom surface of the housing, and an elastic coefficient of the auxiliary buffer component decreases as force applied thereon increases.

According to a physical quantity sensor, a first movable electrode group, a second movable electrode group, a third movable electrode group, and a fourth movable electrode group are arranged in this order along a first direction. In a third direction, a thickness of a second movable electrode in the second movable electrode group and a thickness of a third movable electrode in the third movable electrode group are different from a thickness of a first movable electrode in the first movable electrode group and a thickness of a fourth movable electrode in the fourth movable electrode group. When an imaginary line extending in a second direction from a center of a fixed portion is an axis of symmetry, the first movable electrode is disposed line-symmetrically with the fourth movable electrode, and the second movable electrode is disposed line-symmetrically with the third movable electrode.

A semiconductor device production method includes performing trench etching to form a trench in a thickness direction of a semiconductor layer so that both of a first pattern portion and a second pattern portion whose side walls face each other across the trench are formed. In the trench etching, the semiconductor layer is etched and removed while a protective film is formed on a surface of the semiconductor layer, and the trench etching is performed so that the first pattern portion and the second pattern portion are configured to have a same potential or a same temperature during the trench etching.