A piezoelectric microelectromechanical systems diaphragm microphone can be mounted on a printed circuit board. The microphone can include a substrate with an opening between a bottom end of the substrate and a top end of the substrate. The microphone can have two or more piezoelectric film layers disposed over the top end of the substrate and defining a diaphragm structure. Each of the two or more piezoelectric film layers can have a predefined residual stress that substantially cancel each other out so that the diaphragm structure is substantially flat with substantially zero residual stress. The microphone can include one or more electrodes disposed over the diaphragm structure. The diaphragm structure is configured to deflect when the diaphragm is subjected to sound pressure via the opening in the substrate.

A piezoelectric microelectromechanical systems diaphragm microphone can be mounted on a printed circuit board. The microphone can include a substrate with an opening between a bottom end of the substrate and a top end of the substrate. The microphone can have two or more piezoelectric film layers disposed over the top end of the substrate and defining a diaphragm structure. Each of the two or more piezoelectric film layers can have a predefined residual stress that substantially cancel each other out so that the diaphragm structure is substantially flat with substantially zero residual stress. The microphone can include one or more electrodes disposed over the diaphragm structure. The diaphragm structure is configured to deflect when the diaphragm is subjected to sound pressure via the opening in the substrate.

A microphone assembly comprises a substrate. An acoustic transducer is disposed on the substrate and configured to generate an electrical signal responsive to an acoustic signal. An integrated circuit is disposed on the substrate and electrically coupled to the acoustic transducer. An enclosure is disposed on the substrate, and comprises a main body, and a sidewall projecting axially from outer edges of the main body towards the substrate and contacting the substrate such that an internal volume is defined between the enclosure and the substrate. An insulating layer is insert molded on an inner surface of the enclosure, or over molded on an outer surface of the enclosure such that the insulating layer is not disposed on a portion of the sidewall proximate to the substrate.

Disclosed is a sound vibration sensor using a piezoelectric element having a cantilever structure. The sound vibration sensor includes a housing forming an exterior, a piezoelectric element having a cantilever structure installed in the housing, a support structure supporting a fixed end of the piezoelectric element, a weight attached to a free end of the piezoelectric element, and an energizing part configured to transmit an output from the piezoelectric element, wherein the sound vibration sensor comes into contact with a speaker's body, receives vibration of the body generated when the speaker utters a sound through the housing, and amplifies the vibration by the free end of the piezoelectric element to detect the voice vibration of the speaker using a piezoelectric characteristic of the piezoelectric element.

A robust MEMS transducer includes a kinetic energy diverter disposed within its frontside cavity. The kinetic energy diverter blunts or diverts kinetic energy in a mass of air moving through the frontside cavity, before that kinetic energy reaches a diaphragm of the MEMS transducer. The kinetic energy diverter renders the MEMS transducer more robust and resistant to damage from such a moving mass of air.

A MEMS vibration sensor includes a piezoelectric membrane including a segmented electrode affixed to a holder; and an inertial mass affixed to the piezoelectric membrane, wherein the segmented electrode includes four segmentation zones, wherein, in an X-direction, a signal from a first segmentation zone is equal to a signal from a third segmentation zone, a signal from a second segmentation zone is equal to a signal from a fourth segmentation zone, and the signal from the first segmentation zone and the signal from the second segmentation zone have opposite signs, and wherein, in a Y-direction, a signal from the first segmentation zone is equal to the signal from the second segmentation zone, the signal from the third segmentation zone is equal to the signal from the fourth segmentation zone, and the signal from first segmentation zone and the signal from the third segmentation zone have opposite signs.

A MEMS vibration sensor includes a piezoelectric membrane including a segmented electrode affixed to a holder; and an inertial mass affixed to the piezoelectric membrane, wherein the segmented electrode includes four segmentation zones, wherein, in an X-direction, a signal from a first segmentation zone is equal to a signal from a third segmentation zone, a signal from a second segmentation zone is equal to a signal from a fourth segmentation zone, and the signal from the first segmentation zone and the signal from the second segmentation zone have opposite signs, and wherein, in a Y-direction, a signal from the first segmentation zone is equal to the signal from the second segmentation zone, the signal from the third segmentation zone is equal to the signal from the fourth segmentation zone, and the signal from first segmentation zone and the signal from the third segmentation zone have opposite signs.

A piezoelectric microelectromechanical system microphone comprises a frame, a film of piezoelectric material including slits defining a plurality of independently displaceable piezoelectric elements within an area defined by a perimeter of the frame, bases of the plurality of piezoelectric elements mechanically secured to the frame, tips of the plurality of piezoelectric elements being free to be displaced in a direction perpendicular to a plane defined by the frame responsive to impingement of sound waves on the plurality of piezoelectric elements, and edge extensions extending from edges of the plurality of piezoelectric elements in the direction perpendicular to the plane defined by the frame to reduce a 3 dB roll-off frequency of the piezoelectric microelectromechanical system microphone.

A piezoelectric microelectromechanical system microphone comprises a frame, a film of piezoelectric material including slits defining a plurality of independently displaceable piezoelectric elements within an area defined by a perimeter of the frame, bases of the plurality of piezoelectric elements mechanically secured to the frame, tips of the plurality of piezoelectric elements being free to be displaced in a direction perpendicular to a plane defined by the frame responsive to impingement of sound waves on the plurality of piezoelectric elements, and edge extensions extending from edges of the plurality of piezoelectric elements in the direction perpendicular to the plane defined by the frame to reduce a 3 dB roll-off frequency of the piezoelectric microelectromechanical system microphone.

One of the main objects of the present invention is to provide a MEMS acoustic sensor with improved acoustic performance and liability. To achieve the above-mentioned objects, the present invention provides a MEMS acoustic sensor, including: a base with a cavity; a number of structural layers fixed on the base, each including a fixed end fixed to the base and a suspension end extending from the fixed end for being suspended above the cavity, the suspension end being spaced from the base for forming a slit; a piezoelectric functional layer on the suspension end; and a flexible connector completely covering the slit; wherein a Young's modulus of the flexible connector is smaller than a Young's modulus of the structural layer.