A method of fabricating and packaging an ohmic micro-electro-mechanical system (MEMS) switch device may comprise constructing the switch device on an insulating substrate. The switch device may have contacts that consist of a platinum-group metal. The method may further comprise forming an oxidized layer of the platinum-group metal on an outer surface of each of the one or more contacts. The method may further comprise bonding an insulating cap to the insulating substrate, to hermetically seal the switch device. The bonding may occur in an atmosphere that has a proportion of oxygen within a range of 0.5% to 30%, such that, after the switch device has been hermetically sealed within the sealed cavity, an atmosphere within the sealed cavity has a proportion of oxygen within the range of 0.5% to 30%. The platinum-group metal may be ruthenium, and the oxidized layer of the platinum-group metal may be ruthenium dioxide.

MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.

The present disclosure is directed to a process for manufacturing a micro-electro-mechanical system (MEMS) device. The process includes, in part, forming a first sacrificial dielectric region on a semiconductor wafer; forming a structural layer of semiconductor material on the first sacrificial dielectric region; forming a plurality of first openings through the structural layer; forming a second sacrificial dielectric region on the structural layer; forming a ceiling layer of semiconductor material on the second sacrificial dielectric region; forming a plurality of second openings through the ceiling layer; forming on the ceiling layer a permeable layer; selectively removing the first and the second sacrificial dielectric regions; and forming on the permeable layer a sealing layer of semiconductor material.

A piezoelectric microelectromechanical systems microphone is provided comprising a substrate including at least one wall defining a cavity, the at least one wall defining an anchor region around a perimeter, a piezoelectric film layer forming a membrane, the piezoelectric film layer being supported at the anchor region by a spring region, and an electrode disposed over the piezoelectric film layer. A method of manufacturing such a MEMS microphone is also provided.

A MEMS sensor includes a silicon substrate that has a first surface and a second surface on a side opposite to the first surface and that has a cavity in the first surface, a silicon diaphragm that has a first surface and a second surface on aside opposite to the first surface and in which the second surface is joined directly to the first surface of the silicon substrate, and a piezoresistance formed at the first surface of the silicon diaphragm, and, in the MEMS sensor, a plane orientation of the first surface of the silicon substrate and a plane orientation of the first surface of the silicon diaphragm differ from each other.

The invention relates to a miniature kinetic energy harvester (1) for generating electrical energy, comprising: —a support (2), —a first element (3) having walls (32-35) surrounding at least one cavity (31), —at least one spring (4) mounted between the first element (3) and the support (2), the spring (4) being arranged so that the first element (3) may be brought into oscillation relative to the support (2) according to at least one direction (X) of oscillation, —a transducer (5) arranged between the first element (3) and the support (2) for converting oscillation of the first element (3) relative to the support (2) into an electrical signal, —at least one second element (7) housed within the cavity (31) and mounted to freely move within the cavity (31) relative to the first element (3) so as to impact the walls (32-35) of the cavity (31) when the harvester (1) is subjected to vibrations.

A method embodiment includes providing a MEMS wafer comprising an oxide layer, a MEMS substrate, a polysilicon layer. A carrier wafer comprising a first cavity formed using isotropic etching is bonded to the MEMS, wherein the first cavity is aligned with an exposed first portion of the polysilicon layer. The MEMS substrate is patterned, and portions of the sacrificial oxide layer are removed to form a first and second MEMS structure. A cap wafer including a second cavity is bonded to the MEMS wafer, wherein the bonding creates a first sealed cavity including the second cavity aligned to the first MEMS structure, and wherein the second MEMS structure is disposed between a second portion of the polysilicon layer and the cap wafer. Portions of the carrier wafer are removed so that first cavity acts as a channel to ambient pressure for the first MEMS structure.

A mechanical microsystem including a pair of elastically deformable elements, a mechanical hinge joining the deformable elements together, and at least two electroactive layers. The microsystem is configured such that, from a rest position wherein the deformable elements fall into a plane, a deformation of one of the deformable elements displacing it outside of the plane induces an electric current circulation in one of the two electroactive layers, and/or conversely. Each deformable element has a front face and a rear face opposite one another and substantially parallel to the plane. A first electroactive layer is arranged together with a first deformable element on its rear face, and a second electroactive layer, different from the first layer, is arranged with a second deformable element, different from the first element, on its front face.

Provided are a capacitive transducer that can make a sealing film thickness necessary to seal a gap smaller and can enhance performance such as a wider bandwidth, and a method of manufacturing the capacitive transducer. The capacitive transducer including cells each including a vibration film including a second electrode that is provided with a gap from a first electrode can be manufactured in the following manufacturing method. A convex part is formed on the first electrode, a sacrifice layer having a thickness larger than the thickness of the convex part is formed on the first electrode and the convex part, and a membrane is formed on the sacrifice layer. Further, an etching hole is formed in the membrane at a position above the convex part, the sacrifice layer is etched through the etching hole, and the etching hole is sealed by a sealing layer.

Provided is a sealed cavity structure, including a base; an upper cover fixed to the base in a covering manner and defining a cavity jointly with the base; a leak hole that passes through the upper cover and communicates the cavity with outside; a sealing cover plate attached and fixed to an outer surface of the upper cover and completely covering the leak hole to seal the leak hole; and a sealing cap including a cap wall pressed on a side of the sealing cover plate away from the leak hole and a cap sidewall extending from the cap wall toward a direction close to the upper cover and fixed, in an abutting manner, to the upper cover. A method for manufacturing a sealed cavity structure is further provided. In this technical solution, better sealing reliability can be achieved.