The structure of a micro-electro-mechanical system (MEMS) thermal sensor and a method of fabricating the MEMS thermal sensor are disclosed. A method of fabricating a MEMS thermal sensor includes forming first and second sensing electrodes with first and second electrode fingers, respectively, on a substrate and forming a patterned layer with a rectangular cross-section between a pair of the first electrode fingers. The first and second electrode fingers are formed in an interdigitated configuration and suspended above the substrate. The method further includes modifying the patterned layer to have a curved cross-section between the pair of the first electrode fingers, forming a curved sensing element on the modified patterned layer to couple to the pair of the first electrode fingers, and removing the modified patterned layer.

A microelectromechanical resonator device has: a main body, with a first surface and a second surface, opposite to one another along a vertical axis, and made of a first layer and a second layer, arranged on the first layer; a cap, having a respective first surface and a respective second surface, opposite to one another along the vertical axis, and coupled to the main body by bonding elements; and a piezoelectric resonator structure formed by: a mobile element, constituted by a resonator portion of the first layer, suspended in cantilever fashion with respect to an internal cavity provided in the second layer and moreover, on the opposite side, with respect to a housing cavity provided in the cap; a region of piezoelectric material, arranged on the mobile element on the first surface of the main body; and a top electrode, arranged on the region of piezoelectric material, the mobile element constituting a bottom electrode of the piezoelectric resonator structure.

The structure of a micro-electro-mechanical system (MEMS) thermal sensor and a method of fabricating the MEMS thermal sensor are disclosed. A method of fabricating a MEMS thermal sensor includes forming first and second sensing electrodes with first and second electrode fingers, respectively, on a substrate and forming a patterned layer with a rectangular cross-section between a pair of the first electrode fingers. The first and second electrode fingers are formed in an interdigitated configuration and suspended above the substrate. The method further includes modifying the patterned layer to have a curved cross-section between the pair of the first electrode fingers, forming a curved sensing element on the modified patterned layer to couple to the pair of the first electrodes, and removing the modified patterned layer.

A micromechanical pressure sensor device and a corresponding manufacturing method. The micromechanical pressure sensor device is equipped with a sensor substrate; a diaphragm system that is anchored in the sensor substrate and that includes a first diaphragm and a second diaphragm situated spaced apart therefrom, which are circumferentially connected to one another in an edge area and enclose a reference pressure in an interior space formed in between; and a plate-shaped electrode that is suspended in the interior space and that is situated spaced apart from the first diaphragm and from the second diaphragm and forms a first capacitor with the first diaphragm and forms a second capacitor with the second diaphragm. The first diaphragm and the second diaphragm are designed in such a way that they are deformable toward one another when acted on by an external pressure.

A method of forming a monolithic integrated PMUT and CMOS with a coplanar elastic, sealing, and passivation layer in a single step without bonding and the resulting device are provided. Embodiments include providing a CMOS wafer with a metal layer; forming a dielectric over the CMOS; forming a sacrificial structure in a portion of the dielectric; forming a bottom electrode; forming a piezoelectric layer over the CMOS; forming a top electrode over portions of the bottom electrode and piezoelectric layer; forming a via through the top electrode down to the bottom electrode and a second via down to the metal layer through the top electrode; forming a second metal layer over and along sidewalls of the first and second via; removing the sacrificial structure, an open cavity formed; and forming a dielectric layer over a portion of the CMOS, the open cavity sealed and an elastic layer and passivation formed.

A method of manufacturing an electromechanical systems structure includes manufacturing sub-micron structural features. In some embodiments, the structural features are less than the lithographic limit of a lithography process.

A method of forming an ultrasonic transducer device includes forming a curved membrane over a transducer cavity. A center portion of the curved membrane is closer to a bottom surface of the transducer cavity than with respect to radially outwardly disposed portions of the curved membrane.

A method of manufacturing a semiconductor structure includes providing a first substrate, disposing and patterning a plate over the first substrate, disposing a first sacrificial oxide layer over the plate, forming a plurality of recesses over a surface of the first sacrificial oxide layer, disposing and patterning a membrane over the first sacrificial oxide layer, disposing a second sacrificial oxide layer to surround the membrane and cover the first sacrificial oxide layer; and forming a plurality of conductive plugs passing through the plate or the membrane, wherein the plate includes a semiconductive member and a tensile member, and the semiconductive member is disposed within the tensile member.

A MEMS microphone includes a substrate defining a cavity, a diaphragm being spaced apart from the substrate, covering the cavity, and configured to generate a displacement of the diaphragm in response to an applied acoustic pressure, an anchor extending from an end portion of the diaphragm, and fixed to an upper surface of the substrate to support the diaphragm and a back plate disposed over the diaphragm, the back plate being spaced apart from the diaphragm such that an air gap is maintained between the back plate and the diaphragm, and defining a plurality of acoustic holes, wherein the anchor has a repetitive concave-convex shape in a direction toward a center of the diaphragm so that the anchor acts as a resistance to an acoustic wave.

Methods of forming semiconductor structures comprising one or more cavities, which may be used in the formation of microelectromechanical system (MEMS) transducers, involve forming one or more cavities in a first substrate, providing a sacrificial material within the one or more cavities, bonding a second substrate over a surface of the first substrate, forming one or more apertures through a portion of the first substrate to the sacrificial material, and removing the sacrificial material from within the one or more cavities. Structures and devices are fabricated using such methods.