Abstract: A microelectromechanical systems (MEMS) die includes a substrate, a back plate, and a diaphragm. The back plate is coupled to the substrate and includes a dielectric layer and an electrode. The electrode is coupled to the dielectric layer and defines an opening that exposes a central portion of the dielectric layer. The diaphragm is oriented parallel to the back plate and is spaced apart from the back plate. In one implementation, a diameter of the opening is greater than or equal to 1/10 of the diameter of the diaphragm.

Abstract: A micro-electro-mechanical systems (MEMS) die includes a piston; an electrode facing the piston, wherein a capacitance between the piston and the electrode changes as the distance between the piston and the electrode changes; and a resilient structure (e.g., a gasket or a pleated wall) disposed between the piston and the electrode, wherein the resilient structure supports the piston and resists the movement of the piston with respect to the electrode. A back volume is bounded by the piston and the resilient structure and the resilient structure blocks air from leaving the back volume. The piston may be a rigid body made of a conductive material, such as metal or a doped semiconductor. The MEMS die may also include a second resilient structure, which provides further support to the piston and is disposed within the back volume.

Abstract: A MEMS device can include a first support layer, a second support layer, and a solid dielectric suspended between the first support layer and the second support layer. The solid dielectric can move relative to the first support layer and the second support layer and can include a plurality of apertures. The MEMS device can include a first plurality of electrodes coupled to the first support layer and the second support layer and extending through a first subset of the plurality of apertures. The MEMS device can include a second plurality of electrodes coupled to the first support layer and extending partially into a second subset of the plurality of apertures. The MEMS device can include a third plurality of electrodes coupled to the second support layer and extending partially into a third subset of the plurality of apertures.

Abstract: A first electrode of a MEMS device can be oriented lengthwise along and parallel to an axis, and can have a first end and a second end. A second electrode can be oriented lengthwise along and parallel to the axis and can have a first end and a second end. A third electrode can be oriented lengthwise along and parallel to the axis and can have a first end and a second end. The first, second, and third electrodes can each be located at least partially within an aperture of a plurality of apertures of a solid dielectric that can surround the second electrode second end and the third electrode first end. The second electrode first end and the third electrode second end can be located outside of the solid dielectric.

Abstract: A micro-electromechanical system (MEMS) transducer assembly includes a transducer including a condenser microphone, an integrated circuit electrically connected to the transducer to receive an output voltage from the transducer, wherein the integrated circuit comprises a test signal generator configured to induce a test acoustic response in the transducer, and an evaluation circuit configured to compare the test acoustic response to a baseline acoustic response to identify a fault in the transducer.

Abstract: An implementation of a MEMS device includes a constrained diaphragm comprising a surface, the diaphragm having a net compressive stress; and a backplate comprising a surface facing the surface of the diaphragm, the surface of the backplate having a center, and a post extending from the surface of the backplate, wherein the post is located at or near a center of the surface and limits a maximum deflection of the diaphragm.

Abstract: An acoustic transducer comprises a transducer substrate defining an aperture therein. A diaphragm is disposed on the transducer substrate. The diaphragm comprises a diaphragm inner portion disposed over the aperture such that an outer edge of the diaphragm inner portion is located radially inwards of a rim of the aperture, the diaphragm inner portion having a first stress. A diaphragm outer portion extends radially from the outer edge of the diaphragm inner portion to at least the rim of the aperture, the diaphragm outer portion having a second stress different from the first stress.

Abstract: A microelectromechanical system (MEMS) transducer includes a transducer substrate including an opening; a back plate including a plurality of protrusions oriented substantially perpendicular to the back plate; and a diaphragm between the transducer substrate and the back plate. The diaphragm includes a lead and a plurality of spring members. The lead is structured to suspend the diaphragm over the transducer substrate. The spring members are structured to separate the diaphragm from the transducer substrate and the back plate in the absence of a bias voltage.

Abstract: A capacitive sensor assembly includes a capacitive transduction element and an electrical circuit disposed in the housing and electrically coupled to contacts on an external-device interface of the housing. The electrical circuit includes a sampling circuit having an operational sampling phase during which a voltage produced by the capacitive sensor is sampled by a sampling capacitor coupled to a comparator and an operational charging phase during which a second capacitor is charged by a charge and discharge circuit until the output of the comparator changes state, wherein the output of the sampling circuit is a pulse width modulated signal representative of the voltage on the input of the sampling circuit during each sample period. The output of the sampling circuit can be coupled to a delta-sigma analog-to-digital (A/D) converter.

Abstract: A MEMS transducer for a microphone includes a closed chamber, an array of conductive pins, a dielectric grid, and a diaphragm. The closed chamber is at a pressure lower than atmospheric pressure. The array of conductive pins is in a fixed position in the closed chamber, distributed in two dimensions, and have gaps formed therebetween. The dielectric grid is positioned within the closed chamber, includes a grid of dielectric material positioned between the gaps of the array of conductive pins, and is configured to move parallel to the conductive pins. The diaphragm is configured to form a portion of the closed chamber and deflect in response to changes in a differential pressure between the pressure within the closed chamber and a pressure outside the transducer. The diaphragm is configured to move the dielectric grid relative to the array of conductive pins in response to a change in the differential pressure.

Abstract: A microelectromechanical systems (MEMS) die includes a substrate, a back plate, and a diaphragm. The back plate is coupled to the substrate and includes a dielectric layer and an electrode. The electrode is coupled to the dielectric layer and defines an opening that exposes a central portion of the dielectric layer. The diaphragm is oriented parallel to the back plate and is spaced apart from the back plate. In one implementation, a diameter of the opening is greater than or equal to 1/10 of the diameter of the diaphragm.

Abstract: The problem of contaminants entering a microphone assembly through a pressure equalization aperture is mitigated by moving the pressure equalization aperture from a location near the acoustic port to a location on the cover of the microphone assembly. This is achieved by fabricating an aperture reduction structure using a separate dedicated die, with an aperture of diameter ˜25 microns or less disposed on the aperture reduction structure, and then coupling the aperture reduction structure to the cover of the microphone. The relatively smaller aperture on the cover after the coupling of the aperture reduction structure is used for pressure equalization of the back volume of the microphone with a pressure outside of the microphone assembly.

Abstract: A force feedback actuator includes a pair of electrodes and a dielectric member. The pair of electrodes are spaced apart from one another to form a gap. The dielectric member is disposed at least partially within the gap. The dielectric member includes a first portion having a first permittivity and a second portion having a second permittivity that is different from the first permittivity. The dielectric member and the pair of electrodes are configured for movement relative to each other.

Abstract: An acoustic transducer comprises a transducer substrate defining an aperture therein. A diaphragm is disposed on the transducer substrate. The diaphragm comprises a diaphragm inner portion disposed over the aperture such that an outer edge of the diaphragm inner portion is located radially inwards of a rim of the aperture, the diaphragm inner portion having a first stress. A diaphragm outer portion extends radially from the outer edge of the diaphragm inner portion to at least the rim of the aperture, the diaphragm outer portion having a second stress different from the first stress.

Abstract: A MEMS transducer includes a transducer substrate, a counter electrode, and a diaphragm. The counter electrode is coupled to the transducer substrate. The diaphragm is oriented substantially parallel to the counter electrode and is spaced apart from the counter electrode to form a gap. A back volume of the MEMS transducer is an enclosed volume positioned between the counter electrode and the diaphragm. A height of the gap between the counter electrode and the diaphragm is less than two times the thermal boundary layer thickness within the back volume at an upper limit of the audio frequency band of the MEMS transducer.

Abstract: A micro-electromechanical system (MEMS) transducer assembly includes a transducer including a condenser microphone, an integrated circuit electrically connected to the transducer to receive an output voltage from the transducer, wherein the integrated circuit comprises a test signal generator configured to induce a test acoustic response in the transducer, and an evaluation circuit configured to compare the test acoustic response to a baseline acoustic response to identify a fault in the transducer.

Abstract: The problem of contaminants entering a microphone assembly through a pressure equalization aperture is mitigated by moving the pressure equalization aperture from a location near the acoustic port to a location on the cover of the microphone assembly. This is achieved by fabricating an aperture reduction structure using a separate dedicated die, with an aperture of diameter ˜25 microns or less disposed on the aperture reduction structure, and then coupling the aperture reduction structure to the cover of the microphone. The relatively smaller aperture on the cover after the coupling of the aperture reduction structure is used for pressure equalization of the back volume of the microphone with a pressure outside of the microphone assembly.

Abstract: A microelectromechanical system (MEMS) transducer includes a transducer substrate including an opening; a back plate including a plurality of protrusions oriented substantially perpendicular to the back plate; and a diaphragm between the transducer substrate and the back plate. The diaphragm includes a lead and a plurality of spring members. The lead is structured to suspend the diaphragm over the transducer substrate. The spring members are structured to separate the diaphragm from the transducer substrate and the back plate in the absence of a bias voltage.

Abstract: Methods, systems, and apparatuses for preventing corrosion between dissimilar bonded metals. The method includes providing a wafer having a plurality of circuits, each of the plurality of circuits having a plurality of bond pads including a first metal; applying a coating onto at least the plurality of bond pads; etching a hole in the coating on each of the plurality of bond pads to provide an exposed portion of the plurality of bond pads; dicing the wafer to separate each of the plurality of circuits; die bonding each of the plurality of circuits to a respective packaging substrate; and performing a bonding process to bond a second, dissimilar metal to the exposed portion of each of the plurality of bond pads such that the second, dissimilar metal encloses the hole in the coating of each of the plurality of bond pads, thereby enclosing the exposed portion.

Abstract: A die is manufactured using complementary metal-oxide semiconductor (CMOS) techniques to create transistors, electrical pathways, and microelectromechanical system (MEMS) structures. The MEMS structures include springs, plates, mechanical stops, and structural supports, which can be combined to form complex MEMS structures including microphones, pressure sensors, accelerometers, resonators, gyroscopes, and the like.