A method for forming a MEMS device includes following operations. A first semiconductor layer is formed over a substrate. A plurality of first pillars are formed over the first layer. A second layer is formed over the first pillars and the first layer. A plurality of second pillars are formed over the second layer. A third layer is formed over the second pillars and the second layer.

A microelectromechanical device is provided that includes a mobile rotor and a fixed stator in a device plane. Moreover, a fixed wall defines a wall plane that is adjacent to the device plane and a motion limiter is provided to prevent the rotor from coming into direct physical contact with the fixed wall. The motion limiter includes a shock absorber that extends from the rotor to the stator and a fixed stopper structure that protrudes from the fixed wall toward the shock absorber.

A dual-shell architecture and methods of fabrication of fused quartz resonators is disclosed. The architecture may include two encapsulated and concentric cavities using plasma-activated wafer bonding followed by the high-temperature glassblowing. The dual-shell architecture can provide a protective shield as well as a “fixed-fixed” anchor for the sensing element of the resonators. Structures can be instrumented to operate as a resonator, a gyroscope, or other vibratory sensor and for precision operation in a harsh environment. Methods for fabricating a dual-shell resonator structure can include pre-etching cavities on a cap wafer, pre-etching cavities on a device wafer, bonding the device wafer to a substrate wafer to form a substrate pair and aligning and bonding the cap wafer to the substrate pair to form a wafer stack with aligned cavities including a cap cavity and a device cavity. The wafer stack may be glassblown to form a dual-shell structure.

A method of forming a microelectromechanical device is disclosed wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF conductor and a second RF conductor. The microelectromechanical device further comprises at least a center stack, a first RF stack, a second RF stack, a first stack formed on a first base layer, and a second stack formed on a second base layer, each stack disposed between the beam and the first and second RF conductors. The beam is configured to deflect downward to first contact the first stack formed on the first base layer and the second stack formed on the second base layer simultaneously or the center stack, before contacting the first RF stack and the second RF stack simultaneously.

A microelectromechanical device having a mobile rotor and a fixed stator in a device plane, and a motion limiter that prevents the mobile rotor from contacting a fixed wall in a vertical direction that is perpendicular to the device plane. Moreover, the motion limiter extends between the rotor and the stator and includes a stopper lever that is configured to rotate out of the device plane.

A micromechanical device including a substrate, a movable mass, and a stop spring structure, which includes a stop. The substrate includes a substrate surface in parallel to a main extension plane and the movable mass is situated movably above the substrate surface in relation to the substrate. The stop spring structure is connected to the movable mass. The stop is designed to strike against the substrate surface in the event of a deflection of the movable mass in a z direction, perpendicular to the main extension plane. The stop spring structure, at the location of the stop, includes a first spring constant, a second spring constant, in parallel to the main extension plane, and a third spring constant, in parallel to the main extension plane and perpendicular to the x direction. The first spring constant is greater than the second spring constant and/or is greater than the third spring constant.

In an inertial sensor, a first movable body configured to swing around a first rotation axisrotation axis along a first direction has an opening; the opening includes a second movable body configured to swing around a second rotation axisrotation axis along a second direction, a second support beam supporting the second movable body as the second rotation axisrotation axis, a third movable body configured to swing around a third rotation axisrotation axis along the second direction, and a third support beam supporting the third movable body as the third rotation axisrotation axis; and a protrusion is provided at a surface facing the second movable body and the third movable body, or at the second movable body and the third movable body, the protrusion protruding toward the second movable body and the third movable body or the surface.

A micro-electro-mechanical system (MEMS) microphone is provided. The MEMS microphone includes a substrate, a backplate, an insulating layer, and a diaphragm. The substrate has an opening portion. The backplate is disposed on a side of the substrate, with protrusions protruding toward the substrate. The diaphragm is movably disposed between the substrate and the backplate and spaced apart from the backplate by a spacing distance. The protrusions are configured to limit the deformation of the diaphragm when air flows through the opening portion.

A MEMS inertial sensor includes a supporting structure and an inertial structure. The inertial structure includes at least one inertial mass, an elastic structure, and a stopper structure. The elastic structure is mechanically coupled to the inertial mass and to the supporting structure so as to enable a movement of the inertial mass along a first direction, when the supporting structure is subjected to an acceleration parallel to the first direction. The stopper structure is fixed with respect to the supporting structure and includes at least one primary and one secondary stopper elements. If the acceleration exceeds a first threshold value, the inertial mass abuts against the primary stopper element and subsequently rotates about an axis of rotation defined by the primary stopper element. If the acceleration exceeds a second threshold value, rotation of the inertial mass terminates when the inertial mass abuts against the secondary stopper element.

The invention relates to a microelectromechanical drive for moving an object, having electrostatic bending actuators, wherein each electrostatic bending actuator has a cantilever having at least one active element which has a layer stack forming at least one capacitor positioned offset to a center-of-gravity-plane of the cantilever which leads alongside a longitudinal axis of the cantilever from a supported end of the cantilever to a loose end, which is averted from the supported end of the cantilever and which has a contact area for engaging with the object.

The microelectromechanical drive can be used to displace any target objects from nanoscopic to macroscopic sizes that are within the force-displacement configurations of the electrostatic bending actuators. The microelectromechanical drive is suited to act as an inchworm drive.