An inertia measurement module and three-axis accelerometer, comprising a first pole piece (4) located on a substrate and a mass block (1) suspendingly connected above the substrate via elastic beams (11, 12); the elastic beams (11, 12) includes a first elastic beam (12) and a second elastic beam (11), two ends of the second elastic beams (11) being connected to an anchor point (6) of the substrate, two ends of the first elastic beam (11) being connected to the mass block (1); a center of the first elastic beam (12) and/or the second elastic beam (11) deviates from a center of gravity of the mass block (1); the mass block (1) is further provided with a first movable electrode (9) and a second movable electrode (10) in a Y-axis and an X-axis direction; the movement of one axis in a plane of the inertia measurement module cannot be affected by an eccentric structure feature, such that both X-axis movement and Y-axis movement are linear movements, thus not intensifying an inter-axis coupling, and also not reducing displacement of a mass block on the X-axis and the Y-axis, thus improving capacitance detection precision.

An inertial structure is elastically coupled through a first elastic structure to a supporting structure so as to move along a sensing axis as a function of a quantity to be detected. The inertial structure includes first and second inertial masses which are elastically coupled together by a second elastic structure to enable movement of the second inertial mass along the sensing axis. The first elastic structure has a lower elastic constant than the second elastic structure so that, in presence of the quantity to be detected, the inertial structure moves in a sensing direction until the first inertial mass stops against a stop structure and the second elastic mass can move further in the sensing direction. Once the quantity to be detected ends, the second inertial mass moves in a direction opposite to the sensing direction and detaches the first inertial mass from the stop structure.

The invention relates to an acceleration sensor (400) comprising an excitation mass (420) having excitation electrodes (430), which excitation mass is movably mounted over a substrate (410) along a movement axis (x) and comprising detection electrodes (440) which are permanently connected to the substrate (410) and allocated to the excitation electrodes (430). A first group of pairings (450) of excitation electrode (430) and allocated detection electrodes (440) is suitable for deflecting the excitation mass (420) along the movement axis (x) in a first direction (460). A second group of pairings (450) of excitation electrodes (430) and allocated detection electrodes (440) is suitable for deflecting the excitation mass (420) along the movement axis (x) in a second direction (465), which is opposite the first direction (460). The number of pairings (450) in the first group is equal to the number of pairings (450) in the second group. The averaged distance between excitation electrodes (430) and detection electrodes (440) of the pairings (450) of the first group corresponds to the averaged distance between excitation electrodes (430) and detection electrodes (440) of the pairings (450) of the second group.

A micromechanical sensor that is produced surface-micromechanically includes at least one mass element formed in a third functional layer that is non-perforated at least in certain portions. The sensor has a gap underneath the mass element that is formed by removal of a second functional layer and at least one oxide layer. The removal of the at least one oxide layer takes place by introducing a gaseous etching medium into a defined number of etching channels arranged substantially parallel to one another. The etching channels are configured to be connected to a vertical access channel in the third functional layer.

An acceleration sensor includes a substrate, a support beam, a weight body a stationary section and an engaging section. The weight body is divided into a first weight section and a second weight section based on the support beam as a boundary line, and the first weight section and the second weight section have different weights from each other. The first weight section and the second weight section include a facing section which faces a side of the engaging section opposite to a side facing the support beam. In an X axis direction intersecting the Y axis direction, if a distance between a corner section of the engaging section in the vicinity of one end portion and the support beam is L1 and a distance between the engaging section and the facing section is L2, a relational expression, L1>L2 is satisfied.

In a physical quantity sensor, when a smaller thickness among thicknesses of first fixed electrodes in first fixed electrode portions in a third direction and thicknesses of first movable electrodes in a first movable electrode portion in the third direction is defined as TCA, in a side view in a second direction in a stationary state, one ends of the first movable electrodes on a third direction side are positioned on the third direction side by 4 μm or more and TCA/2 or less relative to one ends of the first fixed electrodes on the third direction side. When an opposite direction of the third direction is defined as a fourth direction, the other ends of the first movable electrodes on a fourth direction side are positioned on the third direction side relative to the other ends of the first fixed electrodes on the fourth direction side.

A physical quantity sensor detects a physical quantity in at least one of a first direction and a second direction. The physical quantity sensor includes a fixed electrode unit provided on a substrate, a movable body including a movable electrode unit provided such that movable electrodes face fixed electrodes of the fixed electrode unit, a fixed portion fixed to the substrate, a support beam having one end coupled to the fixed portion and the other end coupled to the movable body, and a restricting unit configured to restrict displacement of the movable body. The restricting unit includes a first portion having one end coupled to the movable body and extending in the first direction, and a second portion having one end coupled to the other end of the first portion and extending in the second direction.

A MEMS sensor includes: a first substrate having a cavity partially exposed on the surface of the first substrate; an electrode of a sensor element provided on the first substrate and arranged in the cavity; a support portion provided on the first substrate and configured to support the electrode; an element isolation portion formed on the first substrate so as to cover the support portion and configured to electrically isolate the electrode and the support portion from each other; an epitaxial growth layer formed on the electrode and the element isolation portion of the first substrate; and a second substrate bonded to the first substrate and configured to cover the sensor element, wherein the epitaxial growth layer has a monocrystalline portion arranged on the electrode and a polycrystalline portion arranged on the element isolation portion.

A capacitive physical quantity sensor includes a first substrate, a movable electrode, a fixed electrode, and a second substrate. An auxiliary electrode is disposed on a portion of the second substrate to face the movable electrode and the auxiliary electrode has a facing area that faces the movable electrode. The facing area in a case where the movable electrode is displaced in one direction is different from the facing area in a case where the movable electrode is displaced in an opposite direction opposite to the one direction. The physical quantity is detected based on a capacitance, which is generated corresponding to the interval between the fixed electrode and the movable electrode, and a capacitance, which is generated corresponding to an interval between the facing area of the movable electrode and the auxiliary electrode.

A microelectromechanical system (MEMS) acceleration sensor includes a mass bar, a first spring disposed on a first set of opposite sides of the mass bar and configured to secure the mass bar in a first direction, an interdigital structure disposed along a second set of opposite sides of the mass bar in a second direction perpendicular to the first direction, a detection electrode corresponding to the interdigital structure, and a second spring disposed on the second set of opposite sides and configured to secure the mass bar in the second direction. The first spring has a frame shape, and the second spring has an S-shape. Through the second spring, the acceleration sensor is less sensitive to acceleration on the other direction, so that the detection performance of the acceleration sensor is improved.