In one embodiment, a ruggedized wafer level microelectromechanical (“MEMS”) force sensor includes a base and a cap. The MEMS force sensor includes a flexible membrane and a sensing element. The sensing element is electrically connected to integrated complementary metal-oxide-semiconductor (“CMOS”) circuitry provided on the same substrate as the sensing element. The CMOS circuitry can be configured to amplify, digitize, calibrate, store, and/or communicate force values through electrical terminals to external circuitry.

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.

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 complementary metal oxide semiconductor (CMOS) device embedded with micro-electro-mechanical system (MEMS) components in a MEMS region is disclosed. The MEMS components, for example, are infrared (IR) thermosensors. The MEMS sensors are integrated on the CMOS device monolithically after CMOS processing. For example, the MEMS sensors are formed over a BEOL dielectric of a CMOS device. The device is encapsulated with a CMOS compatible IR transparent cap to hermetically seal the MEMS sensors in the MEMS region.

A complementary metal oxide semiconductor (CMOS) device integrated with micro-electro-mechanical system (MEMS) components in a MEMS region is disclosed. The MEMS components, for example, are infrared (IR) thermosensors. The MEMS sensors are integrated on the CMOS device heterogeneously. For example, a CMOS wafer with CMOS devices and interconnections as well as partially processed MEMS modules is bonded with a MEMS wafer with MEMS structures, post CMOS compatibility issues are alleviated. Post integration process to complete the devices includes forming contacts for interconnecting the sensors to the CMOS components as well as encapsulating the devices with a cap wafer using wafer-level vacuum packaging.

Ultrasonic sensing approaches are described with integrated MEMS-CMOS implementations. Embodiments include ultrasonic sensor arrays for which PMUT structures of individual detector elements are at least partially integrated into the CMOS ASIC wafer. MEMS heating elements are integrated with the PMUT structures by integrating under the PMUT structures in the CMOS wafer and/or over the PMUT structures (e.g., in the protective layer). For example, embodiments can avoid wafer bonding and can reduce other post processing involved with conventional manufacturing of PMUT ultrasonic sensors, while also improving thermal response.

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.

A method of forming an ultrasonic transducer device includes forming a patterned metal electrode layer over a substrate, the patterned metal electrode layer comprising a lower layer and an upper layer formed on the lower layer; forming an insulation layer over the patterned metal electrode layer; and planarizing the insulation layer to the upper layer of the patterned metal electrode layer, wherein the upper layer comprises a electrically conductive material that serves as a chemical mechanical polishing (CMP) stop layer that has CMP selectivity with respect to the insulation layer and the lower layer, and wherein the upper layer has a CMP removal rate slower than that of the insulation layer.

Micro-Electro-Mechanical System (MEMS) structures, methods of manufacture and design structures are disclosed. The method includes forming a Micro-Electro-Mechanical System (MEMS) beam structure by venting both tungsten material and silicon material above and below the MEMS beam to form an upper cavity above the MEMS beam and a lower cavity structure below the MEMS beam.

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.