A method and geophysical acceleration sensor (100) for measuring seismic data and also for protecting the sensor from shock. The sensor includes a housing (102); a flexible beam (104) having a first end fixedly attached to the housing; a piezoelectric layer (108) attached to the flexible beam; a seismic mass (112) attached to the flexible beam; and a first movement limiter (130) connected to the housing and configured to limit a movement of the flexible beam. A distance between a tip of the first movement limiter and the flexible beam is adjustable.

Angular accelerometers are described, as are systems employing such accelerometers. The angular accelerometers may include a proof mass and rotational acceleration detection beams directed toward the center of the proof mass. The angular accelerometers may include sensing capabilities for angular acceleration about three orthogonal axes. The sensing regions for angular acceleration about one of the three axes may be positioned radially closer to the center of the proof mass than the sensing regions for angular acceleration about the other two axes. The proof mass may be connected to the substrate though one or more anchors.

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 mechanism for reducing stiction in a MEMS device by decreasing surface area between two surfaces that can come into close contact is provided. Reduction in contact surface area is achieved by increasing surface roughness of one or both of the surfaces. The increased roughness is provided by forming a micro-masking layer on a sacrificial layer used in formation of the MEMS device, and then etching the surface of the sacrificial layer. The micro-masking layer can be formed using nanoclusters. When a next portion of the MEMS device is formed on the sacrificial layer, this portion will take on the roughness characteristics imparted on the sacrificial layer by the etch process. The rougher surface decreases the surface area available for contact in the MEMS device and, in turn, decreases the area through which stiction can be imparted.

A micromechanical component for a sensor device. The component includes a first seismic mass, the first seismic mass displaced out of its first position of rest by a first limit distance into a first direction along a first axis mechanically contacting a first stop structure, and including a second seismic mass which is displaceable out of its second position of rest at least along a second axis, the second axis lying parallel to the first axis or on the first axis, and a second stop surface of the second seismic mass, displaced out of its second position of rest into a second direction counter to the first direction along the second axis, mechanically contacting a first stop surface of the first seismic mass adhering to the first stop structure.

A micromechanical sensor system that includes a mass that is deflectable at least in the z direction. A stop element having an elastic design is situated on the mass on at least one of the sides oriented in the z direction, via a connection element.

The present disclosure provides a composite sensor and a manufacturing method thereof. The composite sensor includes: a first substrate and a second substrate configured to be laminated with the first substrate; a pressure sensor located on the first substrate and configured to sense a change in external pressure; and an acceleration sensor located on the second substrate and configured to sense a change in acceleration. A pressure film of the pressure sensor is configured to be spaced from the second substrate to form a pressure cavity, and a proof mass of the acceleration sensor is configured to be spaced from the first substrate to form a first anti-collision cavity. The present disclosure may reduce the chip area and reduce mutual interference.

Various embodiments of the invention provide for stiction testing in MEMS devices, such as accelerometers. In certain embodiments, testing is accomplished by a high voltage smart circuit that enables an analog front-end circuit to accurately read the position of a movable proof-mass relative to a biased electrode in order to allow the detection of both contact and release conditions. Testing allows to detect actual or potential stiction failures and to reject defective parts in a Final Test stage of a manufacturing process where no other contributors to stiction issue can occur, thereby, minimizing stiction failure risks and extending the reliability of MEMS devices.

An inertial sensor includes: a substrate; a fixing part arranged at one surface of the substrate; a moving element having an opening and configured to swing about a rotation axis along a first direction; a support beam supporting the moving element as the rotation axis in the opening of the moving element; and a support part supporting the support beam. The support part includes a first part fixed to the fixing part, and a second part formed only of a part not fixed to the fixing part. A length in the first direction of the second part is longer than a length in the first direction of the first part.

An inertial sensor includes a substrate, a first supporting beam being a first rotation axis extending along a first direction, a first movable member swingable around the first rotation axis, a second supporting beam being a second rotation axis extending along a second direction crossing the first direction, a second movable member swingable around the second rotation axis, a third rotation axis extending along a second direction, a third movable member swingable around the third rotation axis, and a projection, wherein the second and third movable members are line-symmetrically placed with a center line of the first movable member along the second direction as an axis of symmetry, a center of gravity of the second movable member is closer to the center line than the second supporting beam, and a center of gravity of the third movable member is closer to the center line than the third supporting beam.