Abstract: A MEMS accelerometer includes a proof mass that rotates about an in-plane axis in response to a linear acceleration such that a portion of the proof mass moves out of plane along an out-of-plane axis in a direction of a bump stop. When the proof mass becomes stuck to the bump stop, a signal is applied to one or more anti-stiction electrodes in a manner that moves the proof mass along a movement axis in order to release the proof mass from the bump stop.

Abstract: A MEMS gyroscope may have first and second drive masses configured to be driven in anti-phase. The gyroscope also includes first and second out-of-plane proof masses coupled to the first and second drive masses, respectively. The first and second out-of-plane proof masses may be driven in anti-phase to each other. The first and second out-of-plane proof masses may each include a driven mass and a sense mass, and may be responsive to an angular velocity about an out-of-plane axis to cause a respective in-plane Coriolis forces perpendicular to their respective drive motions. The gyroscope also includes a coupling link between the sense masses of first and second out-of-plane proof masses, which results in rejection of undesired vibrations.

Abstract: A microelectromechanical system (MEMS) accelerometer incorporates deformation sensing with a plurality of sense electrodes positioned to facilitate determining a deformation pattern (e.g., asymmetric or symmetric) of an underlying substrate layer relative to a MEMS layer. The deformation pattern of the substrate layer contributes to offset and/or sensitivity of the accelerometer, so the determination of the deformation pattern enables processing circuitry to compensate and improve offset and/or sensitivity stability. Tilt sense electrodes and/or comparison electrodes may be incorporated alongside the plurality of sense electrodes to monitor deformation of the substrate layer relative to a fixed portion of the MEMS layer.

Abstract: A microelectromechanical (MEMS) sensor, such as an accelerometer, has one more proof masses that respond to movement of the sensor, the movement of which is measured based on a distance between the one or more proof masses and on one or more sense electrodes. The accelerometer also has a plurality of auxiliary electrodes and a signal generator configured to apply an auxiliary signal having a first harmonic frequency to the plurality of auxiliary electrodes. Circuitry receives a sensed signal from the plurality of sense electrodes and identifies a portion of the sensed signal having the first harmonic frequency. Based on this identified portion of the sensed signal, the circuitry determines whether a residual voltage is present on the one or more proof masses or on the one or more sense electrodes, and the circuitry modifies the operation of the accelerometer when the residual voltage is determined to be present in order to compensate for the residual voltage.

Abstract: An actuator layer of a MEMS sensor is be fabricated to include multi-level features, such as additional sense electrodes, vertical bump stops, or weighted proof masses. A sacrificial layer is deposited on the actuator layer such that locations are provided for the multi-level features to extend vertically from the actuator layer. After the multi-layer features are fabricated on the actuator layer the sacrificial layer is removed. Additional processing such as patterning of the actuator layer may be performed to provide desired functionality and electrical signals to portions of the actuator layer, including to the multi-level features.

Abstract: A dual axis accelerometer with a single proof mass measures in-plane acceleration (e.g., either along an x-axis or a y-axis), out-of-plane acceleration (e.g., normal to an x-y plane), and tilt of a fixed portion of a MEMS layer (e.g., normal to the x-y plane). In response to a tilt measurement, the dual-axis accelerometer compensates any offset (e.g., variability) of the out-of-plane accelerometer in order to maintain offset stability. In some embodiments, multiple dual axis accelerometers, perpendicularly configured, may be implemented via processing circuitry to offer three axis sensitivity capability.

Abstract: A microelectromechanical system (MEMS) test structure includes a plurality of capacitors formed from sense electrodes and capacitive plates having a predetermined geometry and size associated with a related MEMS device such as a MEMS sensor. Based on the predetermined relationships between the capacitors of the test structure, and between the test structure and the MEMS devices, an effect of fringing fields on the sensed capacitances of the MEMS devices may be eliminated, and the capacitive gap of the MEMS device may be accurately measured.

Abstract: A MEMS accelerometer package includes multiple cavities such that a change in pressure corresponding to a breach in one or more of the cavities is readily identified based on the output of a pressure-sensitive sensor such as a MEMS resonator. One or more mitigations may be initiated in response to the identification of the change in pressure.

Abstract: A MEMS gyroscope includes a driven mass that moves in response to a drive force. A drive amplitude sense electrode is included as a feature of the drive mass and extends in a direction perpendicular to the drive direction. A change in capacitance is measured based on the relative location of the drive amplitude sense electrode to a known fixed position, which in turn is used to accurately determine a location of the driven mass.

Abstract: A MEMS sensor includes at least one anchor that extends into a MEMS layer and a proof mass suspended from the at least one anchor. Each anchor is coupled to the proof mass via two compliant springs that are oriented perpendicular to each other and attached to a respective anchor. The compliant springs absorb non-measured external forces such as shear forces that are applied to the sensor packaging, preventing these forces from modifying the relative location and operation of the proof mass.

Abstract: A MEMS sensor includes a central anchoring region that maintains the relative position of an attached proof mass relative to sense electrodes in the presence of undesired forces and stresses. The central anchoring region includes one or more first anchors that rigidly couple to a cover substrate and a base substrate. One or more second anchors are rigidly coupled to only the cover substrate and are connected to the one or more first anchors within the MEMS layer via an isolation spring. The proof mass in turn is connected to the one or more second anchors via one or more compliant springs.

Abstract: A MEMS gyroscope includes a driven mass that moves in response to a drive force. A drive amplitude sense electrode is included as a feature of the drive mass and extends in a direction perpendicular to the drive direction. A change in capacitance is measured based on the relative location of the drive amplitude sense electrode to a known fixed position, which in turn is used to accurately determine a location of the driven mass.

Abstract: A gyroscope includes drive portions, lever arms, and proof masses located in a device plane. The lever arms are caused to rotate about an anchoring point based on anti-phase movement of the drive portions along a first axis in the device plane, and are coupled to the proof masses to cause the proof masses to move in anti-phase along an axis perpendicular to the first axis in the device plane. In response to a Coriolis force applied to the proof masses, the lever arm rotates out of plane and the proof masses move relative to sense electrodes. The movement of the proof masses with respect to the sense electrodes is used to measure angular velocity.

Abstract: A microelectromechanical system (MEMS) test structure includes a plurality of capacitors formed from sense electrodes and capacitive plates having a predetermined geometry and size associated with a related MEMS device such as a MEMS sensor. Based on the predetermined relationships between the capacitors of the test structure, and between the test structure and the MEMS devices, an effect of fringing fields on the sensed capacitances of the MEMS devices may be eliminated, and the capacitive gap of the MEMS device may be accurately measured.

Abstract: Exemplary embodiment of a tilting z-axis, out-of-plane sensing MEMS accelerometers and associated structures and configurations are described. Disclosed embodiments facilitate improved offset stabilization. Non-limiting embodiments provide exemplary MEMS structures and apparatuses characterized by one or more of having a sensing MEMS structure that is symmetric about the axis orthogonal to the springs or flexible coupling axis, a spring or flexible coupling axis that is aligned to one of the symmetry axes of the electrodes pattern, a different number of reference electrodes and sense electrodes, a reference MEMS structure having at least two symmetry axes, one which is along the axis of the springs or flexible coupling, and/or a reference structure below the spring or flexible coupling axis.

Abstract: An optimal demodulation phase for extracting an in-phase component of a MEMS gyroscope output signal is determined through a test procedure. During the test procedure, multiple different rotation rate patterns such as different directions of rotation and different rotation rates are applied to the MEMS gyroscope while the MEMS gyroscope output signal is demodulated based on demodulation phases near a predicted quadrature phase for the MEMS gyroscope. The measured gyroscope outputs are used to calculate an optimal demodulation phase for the MEM gyroscope.

Abstract: An integrated MEMS structure includes a driving assembly anchored to a substrate and actuated with a driving movement. A pair of sensing masses suspended above the substrate and coupled to the driving assembly via elastic elements is fixed in the driving movement and performs a movement along a first direction of detection, in response to an external stress. A coupling assembly couples the pair of sensing masses mechanically to couple the vibration modes. The coupling assembly is formed by a rigid element, which connects the sensing masses and has a point of constraint in an intermediate position between the sensing masses, and elastic coupling elements for coupling the rigid element to the sensing masses to present a first stiffness to a movement in phase-opposition and a second stiffness, greater than the first, to a movement in phase, of the sensing masses along the direction of detection.

Abstract: A microelectromechanical (MEMS) sensor, such as an accelerometer, has one more proof masses that respond to movement of the sensor, the movement of which is measured based on a distance between the one or more proof masses and on one or more sense electrodes. The accelerometer also has a plurality of auxiliary electrodes and a signal generator configured to apply an auxiliary signal having a first harmonic frequency to the plurality of auxiliary electrodes. Circuitry receives a sensed signal from the plurality of sense electrodes and identifies a portion of the sensed signal having the first harmonic frequency. Based on this identified portion of the sensed signal, the circuitry determines whether a residual voltage is present on the one or more proof masses or on the one or more sense electrodes, and the circuitry modifies the operation of the accelerometer when the residual voltage is determined to be present in order to compensate for the residual voltage.

Abstract: An optimal demodulation phase for extracting an in-phase component of a MEMS gyroscope output signal is determined through a test procedure. During the test procedure, multiple different rotation rate patterns such as different directions of rotation and different rotation rates are applied to the MEMS gyroscope while the MEMS gyroscope output signal is demodulated based on demodulation phases near a predicted quadrature phase for the MEMS gyroscope. The measured gyroscope outputs are used to calculate an optimal demodulation phase for the MEM gyroscope.

Abstract: A microelectromechanical (MEMS) sensor, such as an accelerometer, has one more proof masses that respond to movement of the sensor, the movement of which is measured based on a distance between the one or more proof masses and on one or more sense electrodes. The accelerometer also has a plurality of auxiliary electrodes and a signal generator configured to apply an auxiliary signal having a first harmonic frequency to the plurality of auxiliary electrodes. Circuitry receives a sensed signal from the plurality of sense electrodes and identifies a portion of the sensed signal having the first harmonic frequency. Based on this identified portion of the sensed signal, the circuitry determines whether a residual voltage is present on the one or more proof masses or on the one or more sense electrodes, and the circuitry modifies the operation of the accelerometer when the residual voltage is determined to be present in order to compensate for the residual voltage.