Representative implementations of techniques and devices provide seals for sealing the joints of bonded microelectronic devices as well as bonded and sealed microelectronic assemblies. Seals are disposed at joined surfaces of stacked dies and wafers to seal the joined surfaces. The seals may be disposed at an exterior periphery of the bonded microelectronic devices or disposed within the periphery using the various techniques.

A thin-film package includes: a substrate; a wiring layer disposed on the substrate; a microelectromechanical systems (MEMS) element disposed on a surface of the substrate; a partition wall disposed on the substrate to surround the MEMS element, and formed of a polymer material; a cap forming a cavity with the substrate and the partition wall; and an external connection electrode connected to the wiring layer. The external connection electrode includes at least one inclined portion disposed on at least one inclined surface formed on any one or any combination of any two or more of the substrate, the partition wall, and the cap.

A bonded structure can include a first element having a first conductive interface feature and a second element having a second conductive interface feature. An integrated device can be coupled to or formed with the first element or the second element. The first conductive interface feature can be directly bonded to the second conductive interface feature to define an interface structure. The interface structure can be disposed about the integrated device in an at least partially annular profile to connect the first and second elements.

A Microelectromechanical systems (MEMS) structure comprises a MEMS wafer. A MEMS wafer includes a handle wafer with cavities bonded to a device wafer through a dielectric layer disposed between the handle and device wafers. The MEMS wafer also includes a moveable portion of the device wafer suspended over a cavity in the handle wafer. Four methods are described to create two or more enclosures having multiple gas pressure or compositions on a single substrate including, each enclosure containing a moveable portion. The methods include: A. Forming a secondary sealed enclosure, B. Creating multiple ambient enclosures during wafer bonding, C. Creating and breaching an internal gas reservoir, and D. Forming and subsequently sealing a controlled leak/breach into the enclosure.

In described examples, a cavity is formed between a substrate and a cap. One or more access holes are formed through the cap for removing portions of a sacrificial layer from within the cavity. A cover is supported by the cap, where the cover is for occulting the one or more access holes along a perspective. An encapsulant seals the cavity, where the encapsulant encapsulates the cover and the one or more access holes.

A liquid-resistant microphone assembly includes a substrate defining a sound-entry region and a microphone transducer coupled with the substrate. The transducer has a sound-responsive region acoustically coupled with the sound-entry opening defined by the substrate. A liquid-resistant port membrane spans across the sound-entry opening defined by the substrate. The membrane is gas-permeable. An adhesive layer is positioned between the substrate and the liquid-resistant port membrane, coupling the liquid-resistant port membrane with the substrate and spacing the liquid-resistant port membrane from the substrate to form a gap between the membrane and the substrate. The adhesive layer defines an aperture having a periphery extending around and positioned outward of the sound-entry region. Modules and electronic devices incorporating such a microphone transducer also are disclosed.

A liquid-resistant microphone assembly includes a substrate defining a sound-entry region and a microphone transducer coupled with the substrate. The transducer has a sound-responsive region acoustically coupled with the sound-entry opening defined by the substrate. A liquid-resistant port membrane spans across the sound-entry opening defined by the substrate. The membrane is gas-permeable. An adhesive layer is positioned between the substrate and the liquid-resistant port membrane, coupling the liquid-resistant port membrane with the substrate and spacing the liquid-resistant port membrane from the substrate to form a gap between the membrane and the substrate. The adhesive layer defines an aperture having a periphery extending around and positioned outward of the sound-entry region. Modules and electronic devices incorporating such a microphone transducer also are disclosed.

A microelectromechanical system (MEMS) device may include a MEMS structure over a first substrate. The MEMS structure comprises a movable element. Depositing a first conductive material over the first substrate and etching trenches in a second substrate. Filling the trenches with a second conductive material and depositing a third conductive material over the second conductive material and the second substrate. Bonding the first substrate and the second substrate and thinning a backside of the second substrate which exposes the second conductive material in the trenches.

The present disclosure relates to a micro-electro mechanical system (MEMS) package and a method of achieving differential pressure adjustment in multiple MEMS cavities at a wafer-to-wafer bonding level. A device substrate comprising first and second MEMS devices is bonded to a capping substrate comprising first and second recessed regions. A ventilation trench is laterally spaced apart from the recessed regions and within the second cavity. A sealing structure is arranged within the ventilation trench and defines a vent in fluid communication with the second cavity. A cap is arranged within the vent to seal the second cavity at a second gas pressure that is different than a first gas pressure of the first cavity.

Devices and techniques include process steps for forming openings through stacked and bonded structures. The openings are formed by pre-etching through one or more layers of prepared dies after planarization of the bonding layer (by chemical-mechanical polishing (CMP) or the like) and prior to bonding. For instance, the openings are etched through one or more layers of dies to be bonded prior to bonding the dies to form an assembly.