A system and method for forming a sensor device with a buried first electrode includes providing a first silicon portion with an electrode layer and a second silicon portion with a device layer. The first silicon portion and the second silicon portion are adjoined along a common oxide layer formed on the electrode layer of the first silicon portion and the device layer of the second silicon portion. The resulting multi-silicon stack includes a buried lower electrode that is further defined by a buried oxide layer, a highly-doped ion implanted region, or a combination thereof. The multi-silicon stack has a plurality of silicon layers and silicon dioxide layers with electrically isolated regions in each layer allowing for both the lower electrode and an upper electrode. The multi-silicon stack further includes a spacer that enables the lower electrode to be accessible from a topside of the sensor device.

A ceramic substrate is mainly constituted of ceramic, and has a first main surface and a second main surface located opposite to the first main surface. A recessed portion recessed toward a first main surface side is formed in the second main surface. A wire portion extending from an outer peripheral surface of the ceramic substrate to inside of the recessed portion is formed, and a bottom portion located on the first main surface side in the recessed portion has a portion thinner than another portion of the ceramic substrate other than the bottom portion.

An array of piezoelectric micromachined ultrasound transducers (PMUTs) includes a substrate having first and second cavities buried therein. A first piezoelectric stack is carried by the substrate and at least partially overlays the first cavity. A second piezoelectric stack is carried by the substrate and at least partially overlays the second cavity. A thickness of the substrate between the second cavity and the second piezoelectric stack forms a membrane. Circuitry operates the second piezoelectric stack so as to vibrate the membrane to generate a pulse of ultrasound and to immediately subsequently operate the first piezoelectric stack to cause deformation of the second cavity which results in an increase in a resonant frequency of the membrane.

A method for forming a MEMS structure includes forming, on a MEMS substrate, an interconnect structure having conductive lines and a first conductive plug of a semiconductor material, forming an etch stop layer on the interconnect structure, forming a dielectric layer over the etch stop layer, bonding a silicon substrate over the dielectric layer, forming a second and third conductive plugs of the semiconductor material in the silicon substrate, wherein the second conductive plug is configured to be electrically coupled with the first conductive plug and third conductive plug is configured to function as an anti-stiction bump, forming a MEMS device electrically coupled with the second conductive feature, and forming a bonding pad on the silicon substrate and surrounded by the second conductive plug.

A surface mount package for a micro-electro-mechanical system (MEMS) microphone die is disclosed. The surface mount package features a substrate with metal pads for surface mounting the package to a device's printed circuit board and for making electrical connections between the microphone package and the device's circuit board. The surface mount microphone package has a cover, and the MEMS microphone die is substrate-mounted and acoustically coupled to an acoustic port provided in the surface mount package. The substrate and the cover are joined together to form the MEMS microphone, and the substrate and cover cooperate to form an acoustic chamber for the substrate-mounted MEMS microphone die.

A bonded structure can include a first element having a first interface feature and a second element having a second interface feature. The first interface feature can be bonded to the second interface feature to define an interface structure. A conductive trace can be disposed in or on the second element. A bond pad can be provided at an upper surface of the first element and in electrical communication with the conductive trace. An integrated device can be coupled to or formed with the first element or the second element.

Methods and systems for MEMS devices with dual damascene formed electrodes is disclosed and may include forming first and second dielectric layers on a semiconductor substrate that includes a conductive layer at least partially covered by the first dielectric layer; removing a portion of the second dielectric layer; forming vias through the second dielectric layer and at least a portion of the second dielectric layer, where the via extends to the conductive layer; forming electrodes by filling the vias and a volume that is the removed portion of the second dielectric layer with a first metal; and coupling a micro-electro-mechanical systems (MEMS) substrate to the semiconductor substrate. A third dielectric layer may be formed between the first and second dielectric layers. A metal pad may be formed on at least one electrode by depositing a second metal on the electrode and removing portions of the second metal, which may be aluminum.

A wiring-buried glass substrate includes a glass substrate and a first wiring. The glass substrate includes a first surface, a second surface perpendicular to the first surface, and a third surface facing the first surface. The first wiring includes a first pillar portion and a first beam portion. The first pillar portion extends in a first direction perpendicular to the first surface of the glass substrate. The first beam portion is connected to a first surface of the first pillar portion and extends to a second direction perpendicular to a second surface of the glass substrate. The first wiring is buried in the glass substrate. The first surface of the first beam portion is exposed from a third surface of the glass substrate.

A microphone assembly is provided, wherein the pre-mold comprises a bent leadframe and a mold body, wherein the mold body is mold to at least partially encapsulate the bent leadframe to build the pre-mold comprising a cavity for accommodating a microphone, and wherein the pre-mold comprises a through-hole transmissive for sound waves.

A surface mount package for a micro-electro-mechanical system (MEMS) microphone die is disclosed. The surface mount package features a substrate with metal pads for surface mounting the package to a device's printed circuit board and for making electrical connections between the microphone package and the device's circuit board. The surface mount microphone package has a cover, and the MEMS microphone die is substrate-mounted and acoustically coupled to an acoustic port provided in the surface mount package. The substrate and the cover are joined together to form the MEMS microphone, and the substrate and cover cooperate to form an acoustic chamber for the substrate-mounted MEMS microphone die.