A capacitive transducer or microphone includes a first substrate of one or more layers and which includes a first surface, a first cavity in the first surface, and a mesa diaphragm that spans the first cavity. The capacitive transducer or microphone includes a second substrate fixed to the first substrate. The second substrate has one or more layers which includes a second cavity having a nonplanar (e.g., contoured or structured or stepped) bottom surface that faces the mesa diaphragm. A shape or relief of the bottom surface of the cavity may advantageously be, to at least some degree, complementary to a deformed shape of the diaphragm. The second substrate may include one or more acoustic holes, non-uniformly distributed thereacross. One or more vents may vent the second cavity.

A method includes forming an etch stop layer over a first side of a device wafer. The method also includes forming a polysilicon layer over the etch stop layer. A handle wafer is fusion bonded to the first side of the device wafer. A eutectic bond layer is formed on a second side of the device wafer. A micro-electro-mechanical system (MEMS) features are etched into the second side of the device wafer to expose the etch stop layer. The exposed etch stop layer is removed to expose the polysilicon layer. The exposed polysilicon layer is removed to expose a cavity formed between the handle wafer and the device wafer.

A method of manufacturing a semiconductive structure includes receiving a first substrate; disposing an interconnection layer on the first substrate; forming a plurality of conductors over the interconnection layer; filing gaps between the plurality of conductors with a film; forming a barrier layer over the film; removing the barrier layer; and partially removing the film to expose a portion of the interconnection and leave a portion of the interconnection layer covered by the film.

In described examples, a bondline structure is arranged along a periphery of a cavity. The bondline structure extends from a first substrate and is configured to bond with an interposer arranged on a second substrate. A diffusion barrier is arranged on the first substrate for contacting the interposer. The diffusion barrier is arranged to impede a contaminant against migrating from the bondline structure and entering the cavity.

A capacitive transducer or microphone includes a first substrate of one or more layers and which includes a first surface, a first cavity in the first surface, and a mesa diaphragm that spans the first cavity. The capacitive transducer or microphone includes a second substrate fixed to the first substrate. The second substrate has one or more layers which includes a second cavity having a nonplanar (e.g., contoured or structured or stepped) bottom surface that faces the mesa diaphragm. A shape or relief of the bottom surface of the cavity may advantageously be, to at least some degree, complementary to a deformed shape of the diaphragm. The second substrate may include one or more acoustic holes, non-uniformly distributed thereacross. One or more vents may vent the second cavity.

Various embodiments of the present disclosure are directed towards a semiconductor device. The semiconductor device includes an interconnect structure disposed over a semiconductor substrate. A dielectric structure is disposed over the interconnect structure. A plurality of cavities are disposed in the dielectric structure. A microelectromechanical system (MEMS) substrate is disposed over the dielectric structure, where the MEMS substrate comprises a plurality of movable membranes, and where the movable membranes overlie the cavities, respectively. A plurality of fluid communication channels are disposed in the dielectric structure, where each of the fluid communication channels extend laterally between two neighboring cavities of the cavities, such that each of the cavities are in fluid communication with one another.

A method for producing a micromechanical device having inclined optical windows, and a corresponding micromechanical device are described. The production method includes: providing a first substrate having a front side and a rear side; forming a plurality of spaced-apart through holes in the first substrate which are arranged along a plurality of spaced-apart rows in the first substrate; forming a respective continuous beveled groove along each of the rows, the grooves defining a seat for the inclined optical windows; and inserting the optical windows into the grooves above the through holes.

A method of forming an ultrasonic transducer device includes forming and patterning a film stack over a substrate, the film stack comprising a metal electrode layer and a chemical mechanical polishing (CMP) stop layer formed over the metal electrode layer; forming an insulation layer over the patterned film stack; planarizing the insulation layer to the CMP stop layer; measuring a remaining thickness of the CMP stop layer; and forming a membrane support layer over the patterned film stack, wherein the membrane support layer is formed at thickness dependent upon the measured remaining thickness of the CMP stop layer, such that a combined thickness of the CMP stop layer and the membrane support layer corresponds to a desired transducer cavity depth.

Methods and systems for improving fusion bonding are disclosed. Plasma treatment is performed on a substrate prior to the fusion bonding, which leaves residual charge on the substrate to be fusion bonded. The residual charge is usually dissipated through an electrically conductive silicone cushion on a loading pin. In the methods, the amount of residual voltage on a test silicon wafer is measured. If the residual voltage is too high, this indicates the usable lifetime of the silicone cushion has passed, and the electrically conductive silicone cushion is replaced. This ensures the continued dissipation of residual charge during use in production, improving the quality of fusion bonds between substrates.

Various embodiments of the present disclosure are directed towards a semiconductor device. The semiconductor device includes an interconnect structure disposed over a semiconductor substrate. A dielectric structure is disposed over the interconnect structure. A plurality of cavities are disposed in the dielectric structure. A microelectromechanical system (MEMS) substrate is disposed over the dielectric structure, where the MEMS substrate comprises a plurality of movable membranes, and where the movable membranes overlie the cavities, respectively. A plurality of fluid communication channels are disposed in the dielectric structure, where each of the fluid communication channels extend laterally between two neighboring cavities of the cavities, such that each of the cavities are in fluid communication with one another.