Abstract: A method of fabricating a die for a microelectromechanical systems (MEMS) microphone includes the steps of forming a diaphragm, etching a plurality of slots through the diaphragm to define a plurality of springs, releasing the diaphragm and the plurality of springs, wherein the plurality of springs relieves intrinsic stress of the diaphragm, and sealing the plurality of slots with sealing material, thereby disabling the springs.

Abstract: A microphone assembly can include a microelectromechanical systems (MEMS) transducer comprising a transducer substrate, a diaphragm oriented substantially parallel to the transducer substrate and spaced apart from the transducer substrate to form a gap, and a counter electrode coupled to the transducer substrate, the counter electrode positioned between the diaphragm and the transducer substrate. The MEMS transducer can generate a signal representative of a change in capacitance between the counter electrode and the diaphragm. A back volume of the MEMS transducer can be an enclosed volume positioned between the transducer substrate and the diaphragm. The microphone assembly can include an integrated circuit that receives the signal, wherein every point within the back volume is less than a thermal boundary layer thickness from a nearest solid surface at an upper limit of an audio frequency band that the integrated circuit is monitoring.

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 system (MEMS) transducer includes a transducer substrate, a diaphragm, and a stiffening member. A first side of the diaphragm is coupled to the transducer substrate. A second side of the diaphragm is coupled to the stiffening member. The stiffening member includes a plurality of fingers extending inwards from a perimeter of an aperture defined by the transducer substrate.

Abstract: A microelectromechanical systems (MEMS) die comprises a first diaphragm having a first side and a second side, and a second diaphragm having a first side facing the first side of the first diaphragm. A first plurality of interconnect strips is disposed along at least the first side of the first diaphragm, a second plurality of interconnect strips is disposed along the first side of the first diaphragm, and a third plurality of interconnect strips is disposed along the first side of the second diaphragm. First, second, and third runner strips are disposed along the second side of the first diaphragm transverse to the first, second, and third plurality of interconnect strips, respectively. Each of the first, second, and third runner strips is electrically connected to at least a subset of the first, second, and third plurality of interconnect strips, respectively, via electrical connections disposed through the first diaphragm.

Abstract: A microelectromechanical systems (MEMS) die includes a first diaphragm and a second diaphragm, wherein the first diaphragm and the second diaphragm bound a sealed chamber. A stationary electrode is disposed within the sealed chamber between the first diaphragm and the second diaphragm. A tunnel passes through the first diaphragm and the second diaphragm without passing through the stationary electrode, wherein the tunnel is sealed off from the chamber. The MEMS die further includes a substrate having an opening formed therethrough, wherein the tunnel provides fluid communication from the opening, through the second diaphragm, and through the first diaphragm.

Abstract: A microelectromechanical systems (MEMS) device comprises a MEMS die that comprises first and second diaphragms, a first plurality of electrodes each disposed on the first diaphragm, and a second plurality of electrodes each disposed on the second diaphragm. A fixed dielectric element is disposed between the first and second diaphragms and includes a plurality of apertures. The MEMS die further comprises a third plurality of electrodes, wherein each of the third plurality comprises a first conductive layer disposed on the first diaphragm proximate to at least one of the first plurality and a second conductive layer disposed on the second diaphragm proximate to at least one of the second plurality, and a conductive pin that extends through an aperture of the plurality of apertures and electrically connects the first conductive layer to the second conductive layer.

Abstract: A MEMS device can include a solid dielectric including a plurality of apertures, the solid dielectric having a first side and a second side. The MEMS device can include a first plurality of electrodes extending completely through a first subset of the plurality of apertures, a second plurality of electrodes extending partially through a second subset of the plurality of apertures, a third plurality of electrodes extending partially into a third subset of the plurality of apertures. The MEMS device can include a first diaphragm coupled to the first plurality and to the third plurality of electrodes, the first diaphragm facing the first side of the solid dielectric. The MEMS device can include a second diaphragm coupled to the first plurality and to the second plurality of electrodes the second diaphragm facing the second side of the solid dielectric.

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 device can include a solid dielectric including a plurality of apertures, the solid dielectric having a first side and a second side. The MEMS device can include a first plurality of electrodes extending completely through a first subset of the plurality of apertures, a second plurality of electrodes extending partially through a second subset of the plurality of apertures, a third plurality of electrodes extending partially into a third subset of the plurality of apertures. The MEMS device can include a first diaphragm coupled to the first plurality and to the third plurality of electrodes, the first diaphragm facing the first side of the solid dielectric. The MEMS device can include a second diaphragm coupled to the first plurality and to the second plurality of electrodes the second diaphragm facing the second side of the solid dielectric.

Abstract: A microelectromechanical systems (MEMS) die includes a first diaphragm and a second diaphragm, wherein the first diaphragm and the second diaphragm bound a sealed chamber. A stationary electrode is disposed within the sealed chamber between the first diaphragm and the second diaphragm. A tunnel passes through the first diaphragm and the second diaphragm without passing through the stationary electrode, wherein the tunnel is sealed off from the chamber. The MEMS die further includes a substrate having an opening formed therethrough, wherein the tunnel provides fluid communication from the opening, through the second diaphragm, and through the first diaphragm.

Abstract: A microphone assembly can include a microelectromechanical systems (MEMS) transducer comprising a transducer substrate, a diaphragm oriented substantially parallel to the transducer substrate and spaced apart from the transducer substrate to form a gap, and a counter electrode coupled to the transducer substrate, the counter electrode positioned between the diaphragm and the transducer substrate. The MEMS transducer can generate a signal representative of a change in capacitance between the counter electrode and the diaphragm. A back volume of the MEMS transducer can be an enclosed volume positioned between the transducer substrate and the diaphragm. The microphone assembly can include an integrated circuit that receives the signal, wherein every point within the back volume is less than a thermal boundary layer thickness from a nearest solid surface at an upper limit of an audio frequency band that the integrated circuit is monitoring.

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: 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 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 microelectromechanical system (MEMS) transducer includes a transducer substrate, a diaphragm, and a stiffening member. A first side of the diaphragm is coupled to the transducer substrate. A second side of the diaphragm is coupled to the stiffening member. The stiffening member includes a plurality of fingers extending inwards from a perimeter of an aperture defined by the transducer substrate.

Abstract: A microelectromechanical systems (MEMS) device comprises a diaphragm assembly and a force feedback system. The diaphragm assembly includes a first diaphragm and a second diaphragm facing the first diaphragm, with a low pressure region being defined therebetween. The diaphragm assembly further includes a first plurality of electrodes, a second plurality of electrodes, and a third plurality of electrodes. A solid dielectric is spaced between the first and second diaphragms and includes a plurality of apertures. Each electrode of the first, second, and third pluralities of electrodes is disposed at least partially within an aperture of the plurality of apertures. The force feedback system receives output from the diaphragm assembly and produces a feedback voltage that is applied to the diaphragm assembly to produce an electrostatic force on the diaphragm assembly that counters a low-frequency pressure across the diaphragm 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: 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 microelectromechanical systems (MEMS) device comprises a diaphragm assembly and a force feedback system. The diaphragm assembly includes a first diaphragm and a second diaphragm facing the first diaphragm, with a low pressure region being defined therebetween. The diaphragm assembly further includes a first plurality of electrodes, a second plurality of electrodes, and a third plurality of electrodes. A solid dielectric is spaced between the first and second diaphragms and includes a plurality of apertures. Each electrode of the first, second, and third pluralities of electrodes is disposed at least partially within an aperture of the plurality of apertures. The force feedback system receives output from the diaphragm assembly and produces a feedback voltage that is applied to the diaphragm assembly to produce an electrostatic force on the diaphragm assembly that counters a low-frequency pressure across the diaphragm assembly.