A micro-electro-mechanical system (MEMS) device includes a supporting substrate, a cavity, a stopper, a MEMS structure, and a bonding dielectric layer. The cavity is located at a top surface of the supporting substrate. The stopper is adjacent to the cavity, where a top surface of the stopper and the top surface of the supporting substrate are on the same level in a height. The MEMS structure is disposed on the supporting substrate, where the MEMS structure includes a proof mass and a suspension beam. The proof mass is disposed directly above the stopper, and the suspension beam is disposed directly above the cavity. The bonding dielectric layer is disposed between the top surface of the supporting substrate and a bottom surface of the MEMS structure.

A piezoelectric microelectromechanical systems microphone is provided comprising a sensor, an anchor region at which the sensor is supported by a substrate, a first region of the sensor adjacent to the anchor region, the first region having at least one piezoelectric layer and at least one electrode, and a second region of the sensor, the second region being adjacent to the first region, having at least one piezoelectric layer and at least one electrode, and having a thickness less than the thickness of the first region. A method for manufacturing a piezoelectric microelectromechanical systems microphone is also provided.

An actuation structure of a MEMS electroacoustic transducer is formed in a die of semiconductor material having a monolithic body with a front surface and a rear surface extending in a horizontal plane x-y plane and defined in which are: a frame; an actuator element arranged in a central opening defined by the frame; cantilever elements, coupled at the front surface between the actuator element and the frame; and piezoelectric regions arranged on the cantilever elements and configured to be biased to cause a deformation of the cantilever elements by the piezoelectric effect. A first stopper arrangement is integrated in the die and configured to interact with the cantilever elements to limit a movement thereof in a first direction of a vertical axis orthogonal to the horizontal plane, x-y plane towards the underlying central opening.

The invention provides a method for manufacturing a MEMS microphone, including the steps of: providing a base and preparing a first diaphragm on a first surface of the base; preparing a back plate on a surface of the first diaphragm opposite to the first surface; forming a first gap between the first diaphragm and the back plate; preparing a second diaphragm; forming a second gap between the second diaphragm and the back plate; preparing electrodes; forming a back cavity by etching the surface opposite to the first surface.

Various embodiments of the present disclosure are directed towards a method for forming an integrated chip, where the method includes forming an interconnect structure over a first substrate. A dielectric structure is formed over the interconnect structure. The dielectric structure comprises opposing sidewalls defining an opening. A conductive bonding structure is formed on a second substrate. A bonding process is performed to bond the conductive bonding structure to the interconnect structure. The conductive bonding structure is disposed in the opening. The bonding process defines a first cavity between inner opposing sidewalls of the conductive bonding structure and a second cavity between the conducive bonding structure and the opposing sidewalls of the dielectric structure.

A semiconductor oxide plate is formed on a recessed surface in a semiconductor matrix material layer. Comb structures are formed in the semiconductor matrix material layer. The comb structures include a pair of inner comb structures spaced apart by a first semiconductor portion. A second semiconductor portion that laterally surrounds the first semiconductor portion is removed selective to the comb structures using an isotropic etch process. The first semiconductor portion is protected from an etchant of the isotropic etch process by the semiconductor oxide plate, the pair of inner comb structures, and a patterned etch mask layer that covers the comb structures. A movable structure for a MEMS device is formed, which includes a combination of the first portion of the semiconductor matrix material layer and the pair of inner comb structures.

Various embodiments of the present disclosure are directed towards a microelectromechanical system (MEMS) device including a conductive bonding structure disposed between a substrate and a MEMS substrate. An interconnect structure overlies the substrate. The MEMS substrate overlies the interconnect structure and includes a moveable membrane. A dielectric structure is disposed between the interconnect structure and the MEMS substrate. The conductive bonding structure is sandwiched between the interconnect structure and the MEMS substrate. The conductive bonding structure is spaced laterally between sidewalls of the dielectric structure. The conductive bonding structure, the MEMS substrate, and the interconnect structure at least partially define a cavity. The moveable membrane overlies the cavity and is spaced laterally between sidewalls of the conductive bonding structure.

A method for manufacturing a micromechanical sensor, including the steps: providing a MEMS wafer that includes a MEMS substrate, a defined number of etching trenches being formed in the MEMS substrate in a diaphragm area, the diaphragm area being formed in a first silicon layer that is situated at a defined distance from the MEMS substrate; providing a cap wafer; bonding the MEMS wafer to the cap wafer; and forming a media access point to the diaphragm area by grinding the MEMS substrate.

Aspects of this disclosure relate to driving a capacitive micromachined ultrasonic transducer (CMUT) with a pulse train of unipolar pulses. The CMUT may be electrically excited with a pulse train of unipolar pulses such that the CMUT operates in a continuous wave mode. In some embodiments, the CMUT may have a contoured electrode.

Aspects of this disclosure relate to a capacitive micromachined ultrasonic transducer (CMUT) with a contoured electrode. In certain embodiments, the CMUT has a contoured electrode. The electrode may be non-planar to correspond to a deflected shape of the outer plate. A change in distance between the electrode and the plate after deflection may be greater than a minimum threshold across the width of the CMUT.