Techniques relating to a micro-electro-mechanical (MEMS) device configured to measure direct axial and shear stress components of a stress tensor are described. The MEMS device includes a first and second circuit configured in a double rosette structure coupled with a third circuit in a standard rosette structure to form a triple rosette piezo-resistive gauge circuit. The first circuit includes at least one piezoresistive element suspended from a substrate, and at least one piezoresistive element fixed to the substrate. The second circuit includes each piezoresistive element fixed to the substrate. The third circuit includes at least one piezoresistive element fixed to the substrate. Additionally, the MEMS device may be coupled to one or more processing systems to determine a mechanical stress tensor that is applied to the MEMS device based on measurements received from the MEMS device.

Disclosed herein is a microelectromechanical device that features a fixed structure defining a cavity, a tiltable structure elastically suspended within the cavity, and a piezoelectrically driven actuation structure that rotates the tiltable structure about a first rotation axis. The actuation structure includes driving arms with piezoelectric material, elastically coupled to the tiltable structure by decoupling elastic elements that are stiff to out-of-plane movements but compliant to torsional movements. The tiltable structure is elastically coupled to the fixed structure at the first rotation axis using elastic suspension elements, while the fixed structure forms a frame surrounding the cavity with supporting elements. A lever mechanism is coupled between a supporting element and a driving arm.

An actuator element of a MEMS device is provided, which is fabricated using surface micromachining on a substrate. An insulating layer having a first portion contacts the substrate while a second portion is separated from the substrate by a gap. A metallic layer contacts the insulating layer having a first portion contacting the first portion of the insulating layer and a second portion contacting the second portion of the insulating layer. The second portion of the metallic layer is prestressed. Alternately, the actuator element includes a first insulating layer separated from the substrate by a gap. A metallic layer has a first portion contacting the substrate and a second portion contacting the insulating layer. A second insulating layer contacts a portion of the second portion of the metallic layer opposite the first insulating layer, where the second insulating layer is prestressed.

Provided herein are multifunctional photoresponsive compositions that can undergo conversion from an aggregation-caused quenching (ACQ) state to an aggregation-induced emission (AIE) state and macroscopic actuation and systems comprising the same and methods of use thereof.

A method of forming a MEMS device includes providing a substrate having a device stopper. The device stopper is integral to the substrate and formed of the substrate material. A thermal dielectric isolation layer may be arranged over the device stopper and the substrate. A device cavity may be formed in the substrate and the thermal dielectric isolation layer. The thermal dielectric isolation layer and the device stopper at least partially surround the device cavity. An active device layer may be formed over the thermal dielectric isolation layer and the device cavity.

A semiconductor device includes a first silicon layer disposed between second and third silicon layers and separated therefrom by respective first and second oxide layers. A cavity within the first silicon layer is bounded by interior surfaces of the second and third silicon layers, and a passageway extends through the second silicon layer to enable material removal from within the semiconductor device to form the cavity. A metal feature is disposed within the passageway to hermetically seal the cavity.

The MEMS actuator is formed by a body, which surrounds a cavity and by a deformable structure, which is suspended on the cavity and is formed by a movable portion and by a plurality of deformable elements. The deformable elements are arranged consecutively to each other, connect the movable portion to the body and are each subject to a deformation. The MEMS actuator further comprises at least one plurality of actuation structures, which are supported by the deformable elements and are configured to cause a translation of the movable portion greater than the deformation of each deformable element. The actuation structures each have a respective first piezoelectric region.

An MEMS includes a substrate having a cavity. The MEMS includes a movable layer arrangement arranged in the cavity including a first beam, a second beam and a third beam that is arranged between the first beam and the second beam and that is fixed at discrete areas electrically insulated from the same. The movable layer arrangement is configured to perform a movement along a direction of movement in a substrate plane in response to an electrical potential between a first beam and a third beam or in response to an electrical potential between the second beam and the third beam. The first, second and third beams are part of a first layer of the movable layer arrangement. The movable layer arrangement includes a second layer arranged adjacent to the first layer along a direction perpendicular to the substrate plane. The second layer is arranged movably along the direction of movement.

Described is a micro-haptic actuator device that can be fabricated with roll-to-roll MEMS processing techniques. The device includes a first body having a first surface and a second, opposing surface, the body has a chamber defined by at least one interior wall, a piston member disposed in the chamber, physically spaced from the at least one interior wall of the chamber, the piston member having a first surface and a second opposing surface. A membrane layer is disposed over and attached to the first surface of the body, with a portion of the membrane attached to the first surface of the piston member. The device also includes a first electrode supported on a second surface the membrane, and a second body that supports a second electrode, with the second body attached to the second surface of the first body.

An actuator element of a MEMS device on a substrate is provided to create large, out-of-plane deflection. The actuator element includes a metallic layer having a first portion contacting the substrate and a second portion having an end proximal to the first portion. A distal end is cantilevered over the substrate. A first insulating layer contacts the metallic layer on a bottom contacting surface of the second cantilevered portion from the proximal to the distal end. A second insulating layer contacts the metallic layer on a portion of a top contacting surface at the distal end. The second portion of the metallic layer is prestressed. A coefficient of thermal expansion of the first and second insulating layers is different than a coefficient of thermal expansion of the metallic layer. And, a Young's modulus of the first and second insulating layer is different than a Young's modulus of the metallic layer.