Abstract: The present disclosure provides a magnetic multi-turn sensor comprising a continuous coil of magnetoresistive elements and a method of manufacturing said sensor. The continuous coil is formed on a substrate such as a silicon wafer that has been fabricated so as to form a trench and bridge arrangement that enables the inner and outer spiral to be connected without interfering with the magnetoresistive elements of the spiral winding in between. Once the substrate has been fabricated with the trench and bridge arrangement, a film of the magnetoresistive material can be deposited to form a continuous coil on the surface of the substrate, wherein a portion of the coil is formed in the trench and a portion of the coil is formed on the bridge.

Abstract: The present disclosure provides a magnetic multi-turn sensor comprising a continuous coil of magnetoresistive elements and a method of manufacturing said sensor. The continuous coil is formed on a substrate such as a silicon wafer that has been fabricated so as to form a trench and bridge arrangement that enables the inner and outer spiral to be connected without interfering with the magnetoresistive elements of the spiral winding in between. Once the substrate has been fabricated with the trench and bridge arrangement, a film of the magnetoresistive material can be deposited to form a continuous coil on the surface of the substrate, wherein a portion of the coil is formed in the trench and a portion of the coil is formed on the bridge.

Abstract: Multiple-axis resonant accelerometers are based on detection of resonance frequency changes of one or more electrostatically-driven resonator masses due to electrostatic gap changes under acceleration. Specifically, one or more resonator masses are configured to resonate simultaneously in different directions associated with different axes of sensitivity (e.g., X, Y, and/or Z axes). The motion of each resonator mass is monitored through one or more electrostatically-coupled sense electrodes. An acceleration along a particular axis of sensitivity causes a small change in the electrostatic gap(s) between the corresponding resonator mass(es) and the sense electrode(s) associated with that axis of sensitivity, and this electrostatic gap change manifests as a small change in the resonance frequency of the resonator from which an accelerometer output signal can be produced.

Abstract: A MEMS product includes a stress-isolated MEMS platform surrounded by a stress-relief gap and suspended from a substrate. The stress-relief gap provides a barrier against the transmission of mechanical stress from the substrate to the platform.

Abstract: An encapsulated MEMS device includes stress-relief trenches in a region of its substrate that surrounds the movable micromachined structures and that is covered by a cap, such that the trenches are fluidly exposed to a cavity between the substrate and the cap. A method of fabricating a MEMS device includes fabricating stress-relief trenches through a substrate and fabricating movable micromachined structures, and capping the device prior art encapsulating the device.

Abstract: Multiple-axis resonant accelerometers are based on detection of resonance frequency changes of one or more electrostatically-driven resonator masses due to electrostatic gap changes under acceleration. Specifically, one or more resonator masses are configured to resonate simultaneously in different directions associated with different axes of sensitivity (e.g., X, Y, and/or Z axes). The motion of each resonator mass is monitored through one or more electrostatically-coupled sense electrodes. An acceleration along a particular axis of sensitivity causes a small change in the electrostatic gap(s) between the corresponding resonator mass(es) and the sense electrode(s) associated with that axis of sensitivity, and this electrostatic gap change manifests as a small change in the resonance frequency of the resonator from which an accelerometer output signal can be produced.

Abstract: An MEMS device has a dynamically variable reference capacitor that provides a reference to a sense capacitance. In some embodiments, a 3-axis accelerometer includes a proof mass suspended above a substrate from an anchor, and a cantilevered Z-axis reference capacitor arm suspended above the substrate from the same anchor. In some embodiments, the proof mass is suspended from a plurality of anchors, and each anchor also supports one or more cantilevered arms, the cantilevered arms forming a dynamically variable reference capacitance.

Abstract: In one aspect, the disclosure is directed to a MEMS device. The MEMS device includes a silicon-based movable MEMS sensor element. The MEMS device also includes a plurality of wells formed into at least one surface of the movable MEMS sensor element. Each well is filled with at least one metal so as to increase the effective mass of the movable MEMS sensor element. The metal may be tungsten or tantalum, or an alloy with tungsten or tantalum.

Abstract: In certain exemplary embodiments of the present invention, rather than having two or more electrodes connected to separate bond pads for making electrical connections to separate electrical circuits to perform various electrode functions (e.g., a drive electrode for performing a drive function and a sense electrode for performing a sense function as in FIG. 1), a common electrode that can perform multiple electrode functions is electrically connected to a single bond pad, with the two electrical circuits connected to the single bond pad. The two electrical circuits are then time-multiplexed so that the electrode can be used for both electrode functions. Among other things, such an arrangement reduces the number of bond pads and therefore allows for reduction of the size of the MEMS die.

Abstract: A MEMS product includes a stress-isolated MEMS platform surrounded by a stress-relief gap and suspended from a substrate. The stress-relief gap provides a barrier against the transmission of mechanical stress from the substrate to the platform.

Abstract: A single-axis tilt-mode microelectromechanical accelerometer structure. The structure includes a substrate having a top surface defined by a first end and a second end. Coupled to the substrate is a first asymmetrically-shaped mass suspended above the substrate pivotable about a first pivot point on the substrate between the first end and the second end and a second asymmetrically-shaped mass suspended above the substrate pivotable about a second pivot point on the substrate between the first end and the second end. The structure also includes a first set of electrodes positioned on the substrate and below the first asymmetrically-shaped mass and a second set of electrodes positioned on the substrate and below the second asymmetrically-shaped mass.

Abstract: An MEMS device has a dynamically variable reference capacitor that provides a reference to a sense capacitance. In some embodiments, a 3-axis accelerometer includes a proof mass suspended above a substrate from an anchor, and a cantilevered Z-axis reference capacitor arm suspended above the substrate from the same anchor. In some embodiments, the proof mass is suspended from a plurality of anchors, and each anchor also supports one or more cantilevered arms, the cantilevered arms forming a dynamically variable reference capacitance.

Abstract: A method of forming a MEMS device provides first and second wafers, where at least one of the first and second wafers has a two-dimensional array of MEMS devices. The method deposits a layer of first germanium onto the first wafer, and a layer of aluminum-germanium alloy onto the second wafer. To deposit the alloy, the method deposits a layer of aluminum onto the second wafer and then a layer of second germanium to the second wafer. Specifically, the layer of second germanium is deposited on the layer of aluminum. Next, the method brings the first wafer into contact with the second wafer so that the first germanium in the aluminum-germanium alloy contacts the second germanium. The wafers then are heated when the first and second germanium are in contact, and cooled to form a plurality of conductive hermetic seal rings about the plurality of the MEMS devices.

Abstract: A MEMS sensor includes a substrate and a MEMS structure coupled to the substrate. The MEMS structure has a mass movable with respect to the substrate. The MEMS sensor also includes a reference structure electrically coupled to the mass of the MEMS sensor. The reference structure is used to provide a reference to offset any environmental changes that may affect the MEMS sensor in order to increase the accuracy of its measurement.

Abstract: One or more electrodes that interact with a movable mass in a MEMS device are anchored or otherwise supported from both the top and bottom and optionally also from one or more of the lateral sides other than the transduction side (i.e., the side of the electrode facing the mass) in order to severely restrict movement of the electrodes such as from interaction with the mass and/or external forces.

Abstract: A single-axis tilt-mode microelectromechanical accelerometer structure. The structure includes a substrate having a top surface defined by a first end and a second end. Coupled to the substrate is a first asymmetrically-shaped mass suspended above the substrate pivotable about a first pivot point on the substrate between the first end and the second end and a second asymmetrically-shaped mass suspended above the substrate pivotable about a second pivot point on the substrate between the first end and the second end. The structure also includes a first set of electrodes positioned on the substrate and below the first asymmetrically-shaped mass and a second set of electrodes positioned on the substrate and below the second asymmetrically-shaped mass.

Abstract: An encapsulated MEMS device includes stress-relief trenches in a region of its substrate that surrounds the movable micromachined structures and that is covered by a cap, such that the trenches are fluidly exposed to a cavity between the substrate and the cap. A method of fabricating a MEMS device includes fabricating stress-relief trenches through a substrate and fabricating movable micromachined structures, and capping the device prior art encapsulating the device.

Abstract: Bulk acoustic wave (BAW) gyroscopes purposefully operate using non-degenerate modes, i.e., resonant frequencies of drive and sense modes are controlled so they are not identical. The resonant frequencies differ by a small controlled amount (?f). The difference (?f) is selected such that the loss of sensitivity, as a result of using non-degenerate modes, is modest. Non-degenerate operation can yield better bandwidth and improves signal-to-noise ratio (SNR) over comparable degenerate mode operation. Increasing Q of a BAW resonator facilitates trading bandwidth for increased SNR, thereby providing a combination of bandwidth and SNR that is better than that achievable from degenerate mode devices. In addition, a split electrode configuration facilitates minimizing quadrature errors in BAW resonators.

Abstract: A MEMS sensing system includes a movable mass having at least one contact surface, a stopper system for stopping the movement of the mass, the stopper system having at least one contact surface that contacts a corresponding contact surface of the mass if a sufficient movement of the mass occurs in a direction, at least one stopper gap formed between the at least one contact surface of the stopper system and the corresponding contact surface of the mass, and a spring system in communication with the at least one stopper gap.

Abstract: A microphone system has a package with an interior, a MEMS microphone within the package interior and forming a backvolume between it and the package interior, and a MEMS valve coupled with at least one input aperture in the package. The package defines at least one input aperture (e.g., the prior noted aperture) for receiving an acoustic signal, and the MEMS microphone is mechanically coupled to at least a portion of one input aperture. The valve has a valve opening generally circumscribed by a valve seat. The valve is considered as having an open mode for permitting acoustic signal access into the package interior through the valve opening, and a closed mode for substantially preventing acoustic signal access into the package interior through the valve opening. The valve has a movable member configured to contact the valve seat when in the closed mode. This movable member is configured to move between the open mode and the closed mode in a direction that is generally perpendicular to the valve seat.