Abstract: A MEMS device includes a drive spring system coupling a pair of drive masses and a sense spring system coupling a pair of sense masses. The drive spring system includes a constrained stiff beam and flexures interconnecting the pair of drive masses. In response to drive movement of the drive masses the flexures enable pivotal movement of the constrained stiff beam about its center hinge point to enable anti-phase drive motion of the drive masses and to suppress in-phase motion of the drive masses. The sense spring system includes diagonally oriented stiff beams and a spring system that enable anti-phase sense motion of the sense masses while suppressing in-phase motion of the sense masses. Coupling masses interposed between the drive and sense masses decouple the drive motion of the drive masses from the sense motion of the sense masses.

Abstract: A MEMS device comprises a substrate, a proof mass spaced apart from a surface of the substrate, and an over-travel stop structure. The over-travel stop structure includes a lateral stop structure and a cap coupled to the lateral stop structure. The MEMS device is fabricated to include relatively small gap sections and relatively large gap regions separating the lateral stop structure from the proof mass. The larger gap regions are covered by the cap and the smaller gap sections are exposed from the gap. During fabrication, removal of particles from the smaller gap sections is facilitated by their exposure from the cap and removal of particles from the larger gap regions underlying the cap is facilitated by their larger size. The lateral stop structure may be cross-shaped to limit deflection of the proof mass along two in-plane axes. The cap limits deflection of the proof mass along an out-of-plane axis.

Abstract: A sensor device comprises a device structure and a cap coupled with the device structure to produce a cavity in which components of the sensor device are located. The device structure includes a substrate and a movable element spaced apart from a surface of the substrate. A port extends through the substrate underlying the movable element. A sense element is spaced apart from the movable element and is displaced away from the port. The movable element and the sense element form an inertial sensor to sense a motion stimulus as movement of the movable element relative to the sense element. An additional sense element together with a diaphragm spans across the port. The movable element and the additional sense element form a pressure sensor for sensing a pressure stimulus from an external environment as movement of the additional sense element together with the diaphragm relative to the movable element.

Abstract: Electrically conductive barriers for integrated circuits and integrated circuits and methods including the electrically conductive barriers. The integrated circuits include a semiconductor substrate, a semiconductor device supported by a device portion of the substrate, and a plurality of bond pads supported by a bond pad portion of the substrate. The integrated circuits also include an electrically conductive barrier that projects away from an intermediate portion of the substrate and is configured to decrease capacitive coupling between the device portion and the bond pad portion. The methods can include methods of manufacturing an integrated circuit. These methods include forming a semiconductor device, forming a plurality of bond pads, forming a plurality of electrically conductive regions, and forming an electrically conductive barrier. The methods also can include methods of operating an integrated circuit.

Abstract: A MEMS device (40) includes a base structure (42) and a microstructure (44) suspended above the structure (42). The base structure (42) includes an oxide layer (50) formed on a substrate (48), a structural layer (54) formed on the oxide layer (50), and an insulating layer (56) formed over the structural layer (54). A sacrificial layer (112) is formed overlying the base structure (42), and the microstructure (44) is formed in another structural layer (116) over the sacrificial layer (112). Methodology (90) entails removing the sacrificial layer (112) and a portion of the oxide layer (50) to release the microstructure (44) and to expose a top surface (52) of the substrate (48). Following removal, a width (86) of a gap (80) produced between the microstructure (44) and the top surface (52) is greater than a width (88) of a gap (84) produced between the microstructure (44) and the structural layer (54).

Abstract: A micro-electro-mechanical system (MEMS) device comprises a micro-electro-mechanical system (MEMS) sensor; a detector circuit; a controller circuit coupled with the MEMS sensor; a first connection arranged between a first output of the MEMS sensor and a first input of the detector circuit; a second connection arranged between a second output of the MEMS sensor and a second input of the detector circuit; and a first switch arranged in the first connection. The controller circuit is configured to open the first switch during a first test mode so as to connect only a single input of the detector circuit with an output of the MEMS sensor. A further switch may be provided to connect two outputs of the MEMS sensor to a single input of the detector circuit.

Abstract: A MEMS device includes a drive spring system coupling a pair of drive masses and a sense spring system coupling a pair of sense masses. The drive spring system includes a constrained stiff beam and flexures interconnecting the pair of drive masses. In response to drive movement of the drive masses the flexures enable pivotal movement of the constrained stiff beam about its center hinge point to enable anti-phase drive motion of the drive masses and to suppress in-phase motion of the drive masses. The sense spring system includes diagonally oriented stiff beams and a spring system that enable anti-phase sense motion of the sense masses while suppressing in-phase motion of the sense masses. Coupling masses interposed between the drive and sense masses decouple the drive motion of the drive masses from the sense motion of the sense masses.

Abstract: A microelectromechanical systems (MEMS) device includes at least two rate sensors (20, 50) suspended above a substrate (30), and configured to oscillate parallel to a surface (40) of the substrate (30). Drive elements (156, 158) in communication with at least one of the rate sensors (20, 50) provide a drive signal (168) exhibiting a drive frequency. One or more coupling spring structures (80, 92, 104, 120) interconnect the rate sensors (20, 50). The coupling spring structures enable oscillation of the rate sensors (20, 50) in a drive direction dictated by the coupling spring structures. The drive direction for the rate sensors (20) is a rotational drive direction (43) associated with a first axis (28), and the drive direction for the rate sensors (50) is a translational drive direction (64) associated with a second axis (24, 26) that is perpendicular to the first axis (28).

Abstract: A system (40) for calibrating an inertial sensor (20) includes a power source (42), a frequency measurement subsystem (44, 48), and a gain determination subsystem (52). A calibration process (110) using the system (40) entails applying (116) a bias voltage (66) to the inertial sensor (20), measuring (114) a drive resonant frequency (46), and measuring (118) a sense resonant frequency (50) of the inertial sensor (20) produced in response to the bias voltage (66). A gain value (32) is determined (124) for calibrating (144) the inertial sensor (20) using a relationship (140) between the sense resonant frequency (50) and the bias voltage (66) without imposing an inertial stimulus on the inertial sensor (20).

Abstract: A MEMS device comprises a substrate, a proof mass spaced apart from a surface of the substrate, and an over-travel stop structure. The over-travel stop structure includes a lateral stop structure and a cap coupled to the lateral stop structure. The MEMS device is fabricated to include relatively small gap sections and relatively large gap regions separating the lateral stop structure from the proof mass. The larger gap regions are covered by the cap and the smaller gap sections are exposed from the gap. During fabrication, removal of particles from the smaller gap sections is facilitated by their exposure from the cap and removal of particles from the larger gap regions underlying the cap is facilitated by their larger size. The lateral stop structure may be cross-shaped to limit deflection of the proof mass along two in-plane axes. The cap limits deflection of the proof mass along an out-of-plane axis.

Abstract: A MEMS pressure sensor device is provided that can provide both a linear output with regard to external pressure, and a differential capacitance output so as to improve the signal amplitude level. These benefits are provided through use of a rotating proof mass that generates capacitive output from electrodes configured at both ends of the rotating proof mass. Sensor output can then be generated using a difference between the capacitances generated from the ends of the rotating proof mass. An additional benefit of such a configuration is that the differential capacitance output changes in a more linear fashion with respect to external pressure changes than does a capacitive output from traditional MEMS pressure sensors.

Abstract: A MEMS pressure sensor device is provided that can provide both a linear output with regard to external pressure, and a differential capacitance output so as to improve the signal amplitude level. These benefits are provided through use of a rotating proof mass that generates capacitive output from electrodes configured at both ends of the rotating proof mass. Sensor output can then be generated using a difference between the capacitances generated from the ends of the rotating proof mass. An additional benefit of such a configuration is that the differential capacitance output changes in a more linear fashion with respect to external pressure changes than does a capacitive output from traditional MEMS pressure sensors.

Abstract: A MEMS device (20) includes a movable element (20) suspended above a substrate (22) by a spring member (34) having a spring constant (104). A spring softening voltage (58) is applied to electrodes (24, 26) facing the movable element (20) during a powered mode (100) to decrease the stiffness of the spring member (34) and thereby increase the sensitivity of the movable element (32) to an input stimulus (46). Upon detection of a stiction condition (112), the spring softening voltage (58) is effectively removed to enable recovery of the movable element (32) from the stiction condition (112). A higher mechanical spring constant (104) yields a stiffer spring (34) having a larger restoring force (122) in the unpowered mode (96) in order to enable recovery from the stiction condition (112). A feedback voltage (56) can be applied to feedback electrodes (28, 30) facing the movable element (32) to provide electrical damping.

Abstract: An inertial sensor (20) includes a movable element (24) coupled to a substrate (28) and adapted for motion about a rotational axis (34). The sensor (20) further includes a trim elements (36, 38). The trim elements (36, 38) are spaced away from a surface (26) of the substrate (28) and are symmetrically positioned on opposing sides of the rotational axis (34). The trim elements (36, 38) are largely insensitive to acceleration about the rotational axis (34), but are sensitive to asymmetrical bending of the substrate (28). Trim signals (72, 74) are received via the trim elements (36, 38) and sense signals (68, 70) are received via sense elements (50, 52). The trim signals (72, 74) are applied to the sense signals (68, 70) to trim an offset error in an output signal of the inertial sensor (20) to produce a compensated sense signal (144).

Abstract: A MEMS sensor includes a movable element spaced apart from a surface of a substrate and fixed sense elements attached to the substrate, where all of the fixed sense elements are oriented parallel to one another. The movable element includes movable sense elements adjacent to the fixed sense elements. The movable element is adapted to undergo motion in response to mutually orthogonal forces, each of the forces being substantially parallel to the surface of the substrate. The fixed sense elements detect the motion of the movable element, and differential logic is applied to determine the magnitudes of the mutually orthogonal forces.

Abstract: An assembly (220) includes a MEMS die (222) and an integrated circuit (IC) die (224) attached to a substrate (226). The MEMS die (222) includes a MEMS device (237) formed on a substrate (242). A packaging process (264) entails forming the MEMS device (237) on the substrate (242) and removing a material portion of the substrate (237) surrounding the device (237) to form a cantilevered substrate platform (246) suspended above the substrate (226) at which the MEMS device (237) resides. The MEMS die (222) is electrically interconnected with the IC die (224). A plug element (314) can be positioned overlying the platform (246). Molding compound (32) is applied to encapsulate the die (222), the IC die (224), and substrate (226). Following encapsulation, the plug element (314) can be removed, and a cap (236) can be coupled to the substrate (242) overlying an active region (244) of the MEMS device (237).

Abstract: A combination sensor and corresponding method of measuring a plurality of environmental parameters uses a pressure sensor disposed on an integrated circuit die; a humidity sensor disposed on the integrated circuit die; and a circuit coupled to and shared by the pressure sensor and the humidity sensor to facilitate pressure and humidity sensing.

Abstract: A system (40) for calibrating an inertial sensor (20) includes a power source (42), a frequency measurement subsystem (44, 48), and a gain determination subsystem (52). A calibration process (110) using the system (40) entails applying (116) a bias voltage (66) to the inertial sensor (20), measuring (114) a drive resonant frequency (46), and measuring (118) a sense resonant frequency (50) of the inertial sensor (20) produced in response to the bias voltage (66). A gain value (32) is determined (124) for calibrating (144) the inertial sensor (20) using a relationship (140) between the sense resonant frequency (50) and the bias voltage (66) without imposing an inertial stimulus on the inertial sensor (20).

Abstract: Methods for fabricating crack resistant Microelectromechanical (MEMS) devices are provided, as are MEMS devices produced pursuant to such methods. In one embodiment, the method includes forming a sacrificial body over a substrate, producing a multi-layer membrane structure on the substrate, and removing at least a portion of the sacrificial body to form an inner cavity within the multi-layer membrane structure. The multi-layer membrane structure is produced by first forming a base membrane layer over and around the sacrificial body such that the base membrane layer has a non-planar upper surface. A predetermined thickness of the base membrane layer is then removed to impart the base membrane layer with a planar upper surface. A cap membrane layer is formed over the planar upper surface of the base membrane layer. The cap membrane layer is composed of a material having a substantially parallel grain orientation.

Abstract: A MEMS sensor (20, 86) includes a support structure (26) suspended above a surface (28) of a substrate (24) and connected to the substrate (24) via spring elements (30, 32, 34). A proof mass (36) is suspended above the substrate (24) and is connected to the support structure (26) via torsional elements (38). Electrodes (42, 44), spaced apart from the proof mass (36), are connected to the support structure (26) and are suspended above the substrate (24). Suspension of the electrodes (42, 44) and proof mass (36) above the surface (28) of the substrate (24) via the support structure (26) substantially physically isolates the elements from deformation of the underlying substrate (24). Additionally, connection via the spring elements (30, 32, 34) result in the MEMS sensor (22, 86) being less susceptible to movement of the support structure (26) due to this deformation.