A silicon substrate having a first silicon substrate having a first surface with a cavity and a second surface opposite the first surface; a first silicon oxide film having a thickness dl on the first surface; a second silicon oxide film having a thickness d2 on a bottom of the cavity; and a third silicon oxide film having a thickness d3 on the second surface, where d1≤d3 and d1<d2, or d3<d1 and d2<d1.

There is disclosed a device and method for fabricating such a device. The device includes cavities formed in a transparent substrate. A laminated membrane is mounted to the substrate and spans the cavities. The laminated membrane includes a layer of a flexible material, typically a polymer, and a layer of a two-dimensional material that is typically graphene.

A method of forming at least one Micro-Electro-Mechanical System (MEMS) includes forming a beam structure and an electrode on an insulator layer, remote from the beam structure. The method further includes forming at least one sacrificial layer over the beam structure, and remote from the electrode. The method further includes forming a lid structure over the at least one sacrificial layer and the electrode. The method further includes providing simultaneously a vent hole through the lid structure to expose the sacrificial layer and to form a partial via over the electrode. The method further includes venting the sacrificial layer to form a cavity. The method further includes sealing the vent hole with material. The method further includes forming a final via in the lid structure to the electrode, through the partial via.

A micromechanical sensor is described that includes: a substrate; a first functional layer that is situated on the substrate; a second functional layer that is situated on the first functional layer and that includes movable micromechanical structures; a cavity in the substrate that is situated below the movable mechanical structures; and a vertical trench structure that surrounds the movable micromechanical structures of the second functional layer and extends into the substrate down to the cavity.

A micromechanical z-inertial sensor having a movable MEMS structure developed in a second function layer; first spring elements developed in a first function layer, and a first electrode developed in the first function layer, the first spring elements being connected to the movable MEMS structure and to a substrate, and the first function layer being situated below the second function layer; second spring elements developed in a third function layer, and a second electrode developed in the third function layer, the second spring elements being connected to the movable MEMS structure and to the substrate, and the third function layer being disposed above the second function layer; the movable MEMS structure being deflectable in the z-direction with the aid of the spring elements, and in a defined manner, not being deflectable in the x- and y-directions.

An integrated circuit assembly including a first wafer bonded to a second wafer with an oxide layer, wherein a first surface of the first wafer is bonded to a first surface of the second wafer. The assembly can include a bonding oxide on a second surface of the second wafer, wherein a surface of the bonding oxide is polished. The assembly can further include a shim secured to the bonding oxide on the second surface of the second wafer to reduce bow of the circuit assembly.

A transducer includes a first piezoelectric layer; and a second piezoelectric layer that is above the first piezoelectric layer; wherein the second piezoelectric layer is a more compressive layer with an average stress that is less than or more compressive than an average stress of the first piezoelectric layer.

A semiconductor device and a method of manufacturing the same are provided. The semiconductor device includes a substrate having a first surface and a second surface arranged opposite to the first surface; a stress-sensitive sensor disposed at the first surface of the substrate, where the stress-sensitive sensor is sensitive to mechanical stress; a stress-decoupling trench that has a vertical extension that extends from the first surface into the substrate, where the stress-decoupling trench vertically extends partially into the substrate towards the second surface although not completely to the second surface; and a plurality of particle filter trenches that vertically extend from the second surface into the substrate, wherein each of the plurality of particle filter trenches have a longitudinal extension that extends orthogonal to the vertical extension of the stress-decoupling trench.

A method of forming at least one Micro-Electro-Mechanical System (MEMS) includes forming a beam structure and an electrode on an insulator layer, remote from the beam structure. The method further includes forming at least one sacrificial layer over the beam structure, and remote from the electrode. The method further includes forming a lid structure over the at least one sacrificial layer and the electrode. The method further includes providing simultaneously a vent hole through the lid structure to expose the sacrificial layer and to form a partial via over the electrode. The method further includes venting the sacrificial layer to form a cavity. The method further includes sealing the vent hole with material. The method further includes forming a final via in the lid structure to the electrode, through the partial via.

A device includes a substrate having first and second layers and an insulator layer between the first and second layers. A microelectromechanical system (MEMS) structure is provide on a portion of the second layer. A trench is formed in the second layer and around at least a part of a periphery of the portion of the second layer. An undercut is formed in the insulator layer and adjacent to the portion of the second layer. The undercut separates the portion of the second layer from the first layer. First and second pinholes extend from a plane of the insulator layer and in the first layer. The first and second pinholes are in fluid communication with the undercut and the trench.