A transducer assembly can include a base. The transducer assembly can include a stress isolation standoff located on the base. The transducer assembly can include a MEMS die disposed on the stress isolation standoff. The transducer assembly can include a die attach adhesive disposed between the MEMS die and the base. The die attach adhesive can bond the MEMS die to the base. The stress isolation standoff can be embedded in the die attach adhesive between the base and the MEMS die.

A capacitive transducer or microphone includes a first substrate of one or more layers and which includes a first surface, a first cavity in the first surface, and a mesa diaphragm that spans the first cavity. The capacitive transducer or microphone includes a second substrate fixed to the first substrate. The second substrate has one or more layers which includes a second cavity having a nonplanar (e.g., contoured or structured or stepped) bottom surface that faces the mesa diaphragm. A shape or relief of the bottom surface of the cavity may advantageously be, to at least some degree, complementary to a deformed shape of the diaphragm. The second substrate may include one or more acoustic holes, non-uniformly distributed thereacross. One or more vents may vent the second cavity.

Embodiments provide a method for acoustically testing at least one MEMS device of a plurality of MEMS devices. The method comprises a step of providing at least one MEMS device. Additionally, the method comprises a step of exciting the at least one MEMS device to an acoustic vibration. Additionally, the method comprises a step of detecting the acoustic vibration of the at least one MEMS device by at least one sound sensor. Additionally, the method comprises a step of evaluating the acoustic vibration of the at least one MEMS device detected by the at least one sound sensor to test the at least one MEMS device as to an intended functionality.

A MEMS device includes a package for providing an inner volume, a MEMS microphone arranged in the inner volume, a sound port through the package to the inner volume, and a passive acoustic attenuation filter acoustically coupled to the sound port.

A microelectromechanical system includes a backplate and a diaphragm. The backplate includes spaced stator elements with voids formed therebetween. The stator element includes a first conductive element. The diaphragm includes a plurality of corrugations facing the voids respectively. Each corrugation includes a groove formed at a surface thereof away from the backplate. The corrugation includes a second conductive element. The diaphragm is moveable with respect to the backplate in response to a pressure exerted thereon to cause the corrugations to be moved into or out of the corresponding voids, thereby changing the capacitance formed between the first and second conductive elements. The corrugations are defined by grooves formed at surfaces away from the backplate, which facilitate to control the compliance of the diaphragm and reduce stiffness of the diaphragm. The corrugation can be formed with lower aspect ratios, which allows it to be formed using standard front side processes.

A method of forming a microphone device includes: forming a through-hole in a substrate wafer; providing a second wafer; bonding the second wafer to the substrate wafer; and forming a top electrode over a first surface of a single-crystal piezoelectric film of the second wafer. The second wafer may include the single-crystal piezoelectric film. The single-crystal piezoelectric film may have a first surface and an opposing second surface. The second wafer may further include a bottom electrode arranged adjacent to the second surface, and a support member over the single-crystal piezoelectric film. The through-hole in substrate wafer may be at least substantially aligned with at least one of the top electrode and the bottom electrode.

The invention provides a MEMS microphone. The MEMS microphone includes a substrate, having a first opening. A dielectric layer is disposed on the substrate, wherein the dielectric layer has a second opening aligned to the first opening. A diaphragm is disposed within the second opening of the dielectric layer, wherein a peripheral region of the diaphragm is embedded into the dielectric layer at sidewall of the second opening. A backplate layer is disposed on the dielectric layer and covering over the second opening. The backplate layer includes a plurality of acoustic holes arranged into a regular array pattern. The regular array pattern comprises a pattern unit, the pattern unit comprises one of the acoustic holes as a center hole, and peripheral holes of the acoustic holes surrounding the center hole with a same pitch to the center hole.

A method for manufacturing a MEMS sound transducer for generating and/or detecting sound waves in the audible wavelength range and/or in the ultrasonic range, includes arranging at least one piezoelectric element on a support substrate. A diaphragm is formed on the at least one piezoelectric element. In forming the diaphragm, a flowable and curable polymer, which forms the diaphragm after curing, is at least partially cast around the at least one piezoelectric element. The invention further relates to the MEMS sound transducer formed by the method.

In an embodiment, a method for manufacturing a micro-electro-mechanical systems (MEMS) transducer device includes providing a substrate body with a surface, depositing an etch-stop layer (ESL) on the surface, depositing a sacrificial layer on the ESL, depositing a diaphragm layer on the sacrificial layer and removing the sacrificial layer, wherein depositing the sacrificial layer includes depositing a first sub-layer of a first material and depositing a second sub-layer of a second material, and wherein the first material and the second material are different materials.

A MEMS sensor includes a sensor package and a membrane arranged in the sensor package, wherein a first partial volume of the sensor package adjoins a first main side of the membrane and a second partial volume of the sensor package adjoins a second main side of the membrane, wherein the second main side is arranged opposite the first main side. The MEMS sensor includes a first opening in the sensor package, said first opening connecting the first partial volume to an external environment of the sensor package in an acoustically transparent fashion. The MEMS sensor includes a second opening in the sensor package, said second opening connecting the second partial volume to the external environment of the sensor package in an acoustically transparent fashion.