A micro-electro-mechanical actuator device includes a fixed structure and a mobile structure. The mobile structure includes a first deformable band, a second deformable band, and a third deformable band, both of which extend on opposite sides of the first deformable band, each of which carries a piezoelectric actuator. In a working condition, in which the second and third piezoelectrics are biased, the second and third deformable bands are subjected to a negative bending, while the first deformable band is subjected to a positive bending. There are thus generated two translations that add together, causing a displacement of the first deformable band greater than the one that may be obtained by a single membrane of an equal base area.

A battery cell includes a case accommodating an electrode assembly, a cap plate covering the case, an electrode terminal disposed on the cap plate and electrically connected to the electrode assembly, and a venting part including an active venting device configure to be opened to discharge gas from inside the case according to an electrical signal generated under a preset condition.

Disclosed herein is a microelectromechanical (MEMS) device, including a rotor and a first piezoelectric actuator mechanically coupled to the rotor. The first piezoelectric actuator is electrically coupled between a first signal node and a common voltage node. A second piezoelectric actuator is mechanically coupled to the rotor, and is electrically coupled between a second signal node and the common voltage node. Control circuitry includes a drive circuit configured to drive the first and second piezoelectric actuators, a sense circuit configured to process sense signals generated by the first and second pizeoelectric actuators, and a multiplexing circuit. The multiplexing circuit is configured to alternate between connecting the drive circuit to the first piezoelectric actuator while connecting the sense circuit to the second piezoelectric actuator, and connecting the drive circuit to the second piezoelectric actuator while connecting the sense circuit to the first piezoelectric actuator.

A micro-electro-mechanical system device is disclosed. The micro-mechanical system device comprises a first silicon substrate comprising: a handle layer comprising a first surface and a second surface, the second surface comprises a cavity; an insulating layer deposited over the second surface of the handle layer; a device layer having a third surface bonded to the insulating layer and a fourth surface; a piezoelectric layer deposited over the fourth surface of the device layer; a metal conductivity layer disposed over the piezoelectric layer; a bond layer disposed over a portion of the metal conductivity layer; and a stand-off formed on the first silicon substrate; wherein the first silicon substrate is bonded to a second silicon substrate, comprising: a metal electrode configured to form an electrical connection between the metal conductivity layer formed on the first silicon substrate and the second silicon substrate.

A MEMS device comprising a body, having a first surface and a second surface; a diaphragm cavity in the body extending from the second surface of the body; a deformable portion in the body between the first surface and the diaphragm cavity; and a piezoelectric actuator, extending on the first surface of the body, over the deformable portion. The MEMS device is characterized in that it comprises a recess structure extending in the body and delimiting a stopper portion for the deformable portion.

A micro-electro-mechanical (MEMS) device is formed in a first wafer overlying and bonded to a second wafer. The first wafer includes a fixed part, a movable part, and elastic elements that elastically couple the movable part and the fixed part. The movable part further carries actuation elements configured to control a relative movement, such as a rotation, of the movable part with respect to the fixed part. The second wafer is bonded to the first wafer through projections extending from the first wafer. The projections may, for example, be formed by selectively removing part of a semiconductor layer. A composite wafer formed by the first and second wafers is cut to form many MEMS devices.

A resonator that includes a vibrating portion that has a piezoelectric film, and a lower and upper electrodes that face each other with the piezoelectric film interposed therebetween. Moreover, a holding portion is provided at least around a maximum displacement region of the vibrating portion and has an insulating film. A holding arm connects the vibrating portion and the holding portion, and include a conductive portion that is in contact with the insulating film of the holding portion in at least a region that faces the maximum displacement region of the vibrating portion. In addition, the conductive portion is electrically connected to the lower electrode or the upper electrode or is grounded.

Systems and techniques are provided for membrane bonding. A photoresist may be applied to an ultrasonic device. A portion of the photoresist may be removed. A bonding agent may be applied a portion of the photoresist that is not removed. A membrane may be placed on the ultrasonic device such that the membrane is in contact with the ultrasonic device through the bonding agent and the photoresist. The membrane and the ultrasonic device may be placed in between a first flat plate and a second flat plate, such that the second flat plate rests on top of the membrane. Light pressure may be applied to the membrane. The light pressure may be applied by one or more of the weight of the second flat plate and a pressure providing device applying pressure to either or both of the first flat plate and the second flat plate.

A physical quantity sensor includes a substrate, a beam part that includes a detection beam, a detection weight that is supported on the substrate through the beam part, and a detection piezoelectric film that is disposed on the detection beam and is configured to generate an electric output according to displacement of the detection beam caused by movement of the detection weight in a direction due to an application of a physical quantity. The detection beam includes a first detection beam and a second detection beam that are disposed to hold the detection weight at different positions from each other in the direction. The first detection beam and the second detection beam have different spring constants, and the detection piezoelectric film is disposed on the first detection beam.

A microelectromechanical structure including a first wafer structure attached by bonding to a second wafer structure. The first wafer structure includes a build part of silicon wafer material, a through via, and an isolation structure separating the through via from the build part. The through via extends between a first electrical contact and a second electrical contact through the first wafer structure in a first direction. The first electrical contact of the first wafer structure is accessible externally and the second electrical contact of the first wafer structure connects to an internal electrical contact on the second wafer structure. In the first direction, the extent of the isolation structure includes a hollow section and a via fill section where the isolation structure is filled with solid electrically insulating material. enables considerable increase of gap height in MEMS structures.