A MEMS structure includes a substrate, an inter-dielectric layer on a front side of the substrate, a MEMS component on the inter-dielectric layer, and a chamber disposed within the inter-dielectric layer and through the substrate. The chamber has an opening at a backside of the substrate. An etch stop layer is disposed within the inter-dielectric layer. The chamber has a ceiling opposite to the opening and a sidewall joining the ceiling. The sidewall includes a portion of the etch stop layer.

A CMOS single chip includes a movable film, at least one support pillar, a base metal layer and a circuit integration. The movable film is disposed on a top layer of the CMOS single chip and has a plurality of through-vias. The support pillar is disposed under the movable film to provide a supporting force of the movable film. The base metal layer is formed under the support pillars and isolated from the support pillars, and faces towards the movable film to form a micro capacitor to sense one of the outside sensing signals. The area of the base metal layer is larger than the area of the movable film. The circuit integration is formed under the base metal layer, or formed under the base metal layer and on the side of the movable film, and connected to the movable film and the base metal layer.

A method for manufacturing a MEMS structure is provided. The method includes providing a MEMS substrate having a first surface, forming a first buffer layer on the first surface of the MEMS substrate, and forming a first roughening layer on the first buffer layer. Also, a MEMS structure is provided. The MEMS structure includes a MEMS substrate, a first buffer layer, a first roughening layer, and a CMOS substrate. The MEMS substrate has a first surface and a pillar is on the first surface. The first buffer layer is on the first surface. The first roughening layer is on the first buffer layer. The CMOS substrate has a second surface and is bonded to the MEMS substrate via the pillar. Moreover, an air gap is between the first roughening layer and the second surface of the CMOS substrate.

A MEMS device formed using the materials of the BEOL of a CMOS process where a post-processing of vHF and post backing was applied to form the MEMS device and where a total size of the MEMS device is between 50 um and 150 um. The MEMS device may be implemented as an inertial sensor among other applications.

Techniques are disclosed for forming group III material-nitride (III-N) microelectromechanical systems (MEMS) structures on a group IV substrate, such as a silicon, silicon germanium, or germanium substrate. In some cases, the techniques include forming a III-N layer on the substrate and optionally on shallow trench isolation (STI) material, and then releasing the III-N layer by etching to form a free portion of the III-N layer suspended over the substrate. The techniques may include, for example, using a wet etch process that selectively etches the substrate and/or STI material, but does not etch the III-N material (or etches the III-N material at a substantially slower rate). Piezoresistive elements can be formed on the III-N layer to, for example, detect vibrations or deflection in the free/suspended portion of the III-N layer. Accordingly, MEMS sensors can be formed using the techniques, such as accelerometers, gyroscopes, and pressure sensors, for example.

A semiconductor device includes a first region; a second region that is peripheral to the first region; a substrate having a first surface and a second surface arranged opposite to the first surface; a stress-sensitive sensor disposed in the first region at the first surface of the substrate; a back end of line (BEOL) stack disposed on the first surface of the semiconductor chip that extends laterally from the MEMS element, in the first region, into the second region; a first cavity formed in the BEOL stack that exposes the sensitive area of the stress-sensitive sensor, wherein the first cavity extends entirely through the BEOL stack over the first region thereby exposing a sensitive area of the stress-sensitive sensor; and at least one stress-decoupling trench laterally spaced from the stress-sensitive sensor and laterally spaced from the first cavity with a portion of the BEOL stack interposed between.

An embodiment is a MEMS device including a first MEMS die having a first cavity at a first pressure, a second MEMS die having a second cavity at a second pressure, the second pressure being different from the first pressure, and a molding material surrounding the first MEMS die and the second MEMS die, the molding material having a first surface over the first and the second MEMS dies. The device further includes a first set of electrical connectors in the molding material, each of the first set of electrical connectors coupling at least one of the first and the second MEMS dies to the first surface of the molding material, and a second set of electrical connectors over the first surface of the molding material, each of the second set of electrical connectors being coupled to at least one of the first set of electrical connectors.

A semiconductor device and a method of manufacturing the same are provided. The semiconductor device includes a semiconductor chip including 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, wherein the stress-sensitive sensor is sensitive to mechanical stress; a first pair of adjacent stress-decoupling trenches arranged laterally from a first lateral side of the stress-sensitive sensor, where each stress-decoupling trench of the first pair of adjacent stress-decoupling trenches extends partially from the first surface into the substrate towards the second surface although not completely to the second surface; and a first spring structure formed between the first pair of adjacent stress-decoupling trenches such that the first spring structure is arranged laterally from the stress-sensitive sensor and is configured to absorb external stress from an environment.

Representative methods for sealing MEMS devices include depositing insulating material over a substrate, forming conductive vias in a first set of layers of the insulating material, and forming metal structures in a second set of layers of the insulating material. The first and second sets of layers are interleaved in alternation. A dummy insulating layer is provided as an upper-most layer of the first set of layers. Portions of the first and second set of layers are etched to form void regions in the insulating material. A conductive pad is formed on and in a top surface of the insulating material. The void regions are sealed with an encapsulating structure. At least a portion of the encapsulating structure is laterally adjacent the dummy insulating layer, and above a top surface of the conductive pad. An etch is performed to remove at least a portion of the dummy insulating layer.

A semiconductor device and a method of manufacturing the same are provided. The semiconductor device includes a semiconductor chip including 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, wherein the stress-sensitive sensor is sensitive to mechanical stress; a first pair of adjacent stress-decoupling trenches arranged laterally from a first lateral side of the stress-sensitive sensor, where each stress-decoupling trench of the first pair of adjacent stress-decoupling trenches extends partially from the first surface into the substrate towards the second surface although not completely to the second surface; and a first spring structure formed between the first pair of adjacent stress-decoupling trenches such that the first spring structure is arranged laterally from the stress-sensitive sensor and is configured to absorb external stress from an environment.