Abstract: A microelectromechanical systems (MEMS) sensor (20) includes a substrate (26) and suspension anchors (34, 36) formed on a planar surface (28) of the substrate (26). The MEMS sensor (20) further includes a first movable element (38) and a second movable element (40) suspended above the substrate (26). Compliant members (42, 44) interconnect the first movable element (38) with the suspension anchor 34 and compliant members (46, 48) interconnect the second movable element (40) with the suspension anchor (36). The movable elements (38, 40) have an equivalent shape. The movable elements may be generally rectangular movable elements (38, 40) or L-shaped movable elements (108, 110) in a nested configuration. The movable elements (38, 40) are oriented relative to one another in rotational symmetry about a point location (94) on the substrate (26).

Abstract: A microelectromechanical systems (MEMS) sensor (40) includes a substrate (46) and a suspension anchor (54) formed on a planar surface (48) of the substrate (46). A first folded torsion spring (58) and a second folded torsion spring (60) interconnect the movable element (56) with the suspension anchor (54) to suspend the movable element (56) above the substrate (46). The folded torsion springs (58, 60) are each formed from multiple segments (76) that are linked together by bar elements (78) in a serpentine fashion. The folded torsion springs (58, 60) have an equivalent shape and are oriented relative to one another in rotational symmetry about a centroid (84) of the suspension anchor (54).

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: An accelerometer (50, 100, 120, 130) includes a substrate (58) and a proof mass (54) spaced apart from a surface (56) of the substrate (58). Compliant members (62) are coupled to the proof mass (54) and enable the proof mass (54) to move parallel to the surface (56) of the substrate (58) in a sense direction (68). Proof mass anchors (60) interconnect the compliant members (62) with the surface (56). The accelerometer (50, 100, 120, 130) includes an over-travel stop structure (52, 102, 122, 132) having stop anchors (70, 72) coupled to the substrate (58). The stop anchors (70, 72) are coupled to the substrate (58) at positions (76) on the surface (56) residing at least partially within an anchor attach area (71) bounded in the sense direction (68) by locations (78) of the proof mass anchors (60) on the surface (56).

Abstract: A microelectromechanical systems (MEMS) capacitive sensor (52) includes a movable element (56) pivotable about a rotational axis (68) offset between ends (80, 84) thereof. A static conductive layer (58) is spaced away from the movable element (56) and includes electrode elements (62, 64). The movable element (56) includes a section (74) between the rotational axis (68) and one end (80) that exhibits a length (78). The movable element (56) further includes a section (76) between the rotational axis (68) and the other end (84) that exhibits a length (82) that is less than the length (78) of the section (74). The section (74) includes slots (88) extending through movable element (56) from the end (80) toward the rotational axis (68). The slots (88) provide stress relief in section (74) that compensates for package stress to improve sensor performance.

Abstract: A microelectromechanical systems (MEMS) sensor (52) includes a substrate (62) a movable element (58) spaced apart from the substrate (62), suspension anchors (66, 68, 70, 72) formed on the substrate (62), and compliant members (74) interconnecting the movable element (58) with the suspension anchors. The MEMS sensor (52) further includes fixed fingers (76) and fixed finger anchors (78) attaching the fixed fingers (76) to the substrate (62). The movable element (58) includes openings (64). At least one of the suspension anchors resides in at least one of the multiple openings (64) and pairs (94) of the fixed fingers (76) reside in other multiple openings (64). The MEMS sensor (52) is symmetrically formed, and a location of the fixed finger anchors (78) defines an anchor region (103) within which the suspension anchors (66, 68, 70, 72) are positioned.

Abstract: A microelectromechanical systems (MEMS) transducer (90) is adapted to sense acceleration in mutually orthogonal directions (92, 94, 96). The MEMS transducer (90) includes a proof mass (100) suspended above a substrate (98) by an anchor system (116). The anchor system (116) pivotally couples the proof mass (100) to the substrate (98) at a rotational axis (132) to enable the proof mass (100) to rotate about the rotational axis (132) in response to acceleration in a direction (96). The proof mass (100) has an opening (112) extending through it. Another proof mass (148) resides in the opening (112), and another anchor system (152) suspends the proof mass (148) above the surface (104) of the substrate (98). The anchor system (152) enables the proof mass (148) to move substantially parallel to the surface (104) of the substrate (98) in response to acceleration in at least another direction (92, 94).

Abstract: A microelectromechanical systems (MEMS) sensor device (20) includes a substrate (22) having sensors (24, 26) disposed on the same side (28) of the substrate (22) and laterally spaced apart from one another. The sensor (26) includes a sense element (56), and the substrate (22) includes a cavity (58) extending through the substrate (22) from the backside (30) of the substrate (22) to expose the sense element (56) to an external environment (54). The sense element (56) is movable in response to a stimulus (52) from the environment (54) due to its exposure to the environment (54) via the cavity (58). Fabrication methodology (66) entails concurrently forming the sensors (24, 26) on substrate (22) by implementing MEMS process flow, followed by creating the cavity (58) through the substrate (22) to expose the sense element (56) to the environment (54).

Abstract: An accelerometer (50, 100, 120, 130) includes a substrate (58) and a proof mass (54) spaced apart from a surface (56) of the substrate (58). Compliant members (62) are coupled to the proof mass (54) and enable the proof mass (54) to move parallel to the surface (56) of the substrate (58) in a sense direction (68). Proof mass anchors (60) interconnect the compliant members (62) with the surface (56). The accelerometer (50, 100, 120, 130) includes an over-travel stop structure (52, 102, 122, 132) having stop anchors (70, 72) coupled to the substrate (58). The stop anchors (70, 72) are coupled to the substrate (58) at positions (76) on the surface (56) residing at least partially within an anchor attach area (71) bounded in the sense direction (68) by locations (78) of the proof mass anchors (60) on the surface (56).

Abstract: A microelectromechanical systems (MEMS) transducer (90) is adapted to sense acceleration in mutually orthogonal directions (92, 94, 96). The MEMS transducer (90) includes a proof mass (100) suspended above a substrate (98) by an anchor system (116). The anchor system (116) pivotally couples the proof mass (100) to the substrate (98) at a rotational axis (132) to enable the proof mass (100) to rotate about the rotational axis (132) in response to acceleration in a direction (96). The proof mass (100) has an opening (112) extending through it. Another proof mass (148) resides in the opening (112), and another anchor system (152) suspends the proof mass (148) above the surface (104) of the substrate (98). The anchor system (152) enables the proof mass (148) to move substantially parallel to the surface (104) of the substrate (98) in response to acceleration in at least another direction (92, 94).

Abstract: A MEMS device that has a sensitivity to a stimulus in at least one sensing direction includes a substrate, a movable mass with corner portions suspended in proximity to the substrate, at least one suspension structure coupled approximately to the corner portions of the movable mass for performing a mechanical spring function, and at least one anchor for coupling the substrate to the at least one suspension structure. The at least one anchor is positioned approximately on a center line in the at least one sensing direction.

Abstract: A MEMS device includes a substrate; a movable mass suspended in proximity to the substrate; and at least one suspension structure coupled to the movable mass for performing a mechanical spring function. The at least one suspension structure has portions that move in tandem when the MEMS device is subject to at least one stimulus in a sensing direction, and further includes at least one link between the portions that move in tandem.

Abstract: A microelectromechanical systems (MEMS) capacitive sensor (52) includes a movable element (56) pivotable about a rotational axis (68) offset between ends (80, 84) thereof. A static conductive layer (58) is spaced away from the movable element (56) and includes electrode elements (62, 64). The movable element (56) includes a section (74) between the rotational axis (68) and one end (80) that exhibits a length (78). The movable element (56) further includes a section (76) between the rotational axis (68) and the other end (84) that exhibits a length (82) that is less than the length (78) of the section (74). The section (74) includes slots (88) extending through movable element (56) from the end (80) toward the rotational axis (68). The slots (88) provide stress relief in section (74) that compensates for package stress to improve sensor performance.

Abstract: A microelectromechanical systems (MEMS) sensor (52) includes a substrate (62) a movable element (58) spaced apart from the substrate (62), suspension anchors (66, 68, 70, 72) formed on the substrate (62), and compliant members (74) interconnecting the movable element (58) with the suspension anchors. The MEMS sensor (52) further includes fixed fingers (76) and fixed finger anchors (78) attaching the fixed fingers (76) to the substrate (62). The movable element (58) includes openings (64). At least one of the suspension anchors resides in at least one of the multiple openings (64) and pairs (94) of the fixed fingers (76) reside in other multiple openings (64). The MEMS sensor (52) is symmetrically formed, and a location of the fixed finger anchors (78) defines an anchor region (103) within which the suspension anchors (66, 68, 70, 72) are positioned.

Abstract: A differential capacitive sensor (50) includes a movable element (56) pivotable about a rotational axis (60). The movable element (56) includes first and second sections (94, 96). The first section (94) has an extended portion (98) distal from the rotational axis (60). A static layer (52) is spaced away from a first surface (104) of the moveable element (56), and includes a first actuation electrode (74), a first sensing electrode (64), and a third sensing electrode (66). A static layer (62) is spaced away from a second surface (106) of the moveable element (56) and includes a second actuation electrode (74), a second sensing electrode (70), and a fourth sensing electrode (72). The first and second electrodes (64, 70) oppose the first section (94), the third and fourth electrodes (66, 72) oppose the second section (96), and the first and second electrodes (68, 74) oppose the extended portion (98).

Abstract: A resonant accelerometer (24) includes a single anchor (28) fixed to a substrate (32). A proof mass (34) is positioned above a surface (30) of the substrate (32) and is positioned symmetrically about the anchor (28). The proof mass (34) has a central opening (38). Each of a number of suspension beams (42, 44, 46, 48) resides in the central opening (38) and has one end (50) affixed to the anchor (28) and another end (52) attached to an inner peripheral wall (40) of the proof mass (34). A resonant frequency of the beams (42, 44) in a direction (64) aligned with a common axis (58) of the beams (42, 44) changes according to acceleration in the direction (64). A resonant frequency of the beams (46, 48) in a direction (66) aligned with a common axis (62) of the beams (46, 48) changes according to acceleration in the direction (66).

Abstract: A symmetrical differential capacitive sensor (60) includes a movable element (66) pivotable about a geometrically centered rotational axis (70). The element (66) includes sections (86, 88). Each of the sections (86, 88) has a stop (94, 96) spaced equally away from the rotational axis (70). Each of the sections (86, 88) also has a different configuration (104, 108) of apertures (102, 106). The configurations (104, 108) of apertures (102, 106) create a mass imbalance between the sections (86, 88) so that the element (66) pivots about the rotational axis (70) in response to acceleration. The apertures (102, 106) also facilitate etch release during manufacturing and reduce air damping when the element (66) rotates. Apertures (126, 128) are formed in electrodes (78, 80) underlying the apertures (102, 106) to match the capacitance between the two sections (86, 88) of movable element (86) to provide the same bi-directional actuation capability.

Abstract: A capacitor assembly (82) is formed on a substrate (20). The capacitor assembly a first conductive plate (38) and a second conductive plate (60) formed over the substrate such that the second conductive plate is separated from the first conductive plate by a distance. A conductive trace (40) is formed over the substrate that is connected to the first conductive plate and extends away from the capacitor assembly. A conductive shield (62) is formed over at least a portion of the conductive trace that is separated from the first and second conductive plates to control a fringe capacitance between the second conductive plate and the conductive trace.

Abstract: A transducer (20) includes a movable element (24), a self-test actuator (22), and a sensing element (56, 58). The sensing element (56, 58) detects movement of the movable element (24) from a first position (96) to a second position (102) along an axis perpendicular to a plane of the sensing element (56, 58). The second position (102) results in an output signal (82) that simulates a free fall condition. A method (92) for testing a protection feature of a device (70) having the transducer (20) entails moving the movable element (24) to the first position (102) to produce a negative gravitational force detectable at the sensing element (56, 68), applying a signal (88) to the actuator (22) to move the movable element (24) to the second position (102) by the electrostatic force (100) , and ascertaining an enablement of the protection feature in response to the simulated free fall.

Abstract: A symmetrical differential capacitive sensor (60) includes a movable element (66) pivotable about a geometrically centered rotational axis (70). The element (66) includes sections (86, 88). Each of the sections (86, 88) has a stop (94, 96) spaced equally away from the rotational axis (70). Each of the sections (86, 88) also has a different configuration (104, 108) of apertures (102, 106). The configurations (104, 108) of apertures (102, 106) create a mass imbalance between the sections (86, 88) so that the element (66) pivots about the rotational axis (70) in response to acceleration. The apertures (102, 106) also facilitate etch release during manufacturing and reduce air damping when the element (66) rotates. Apertures (126, 128) are formed in electrodes (78, 80) underlying the apertures (102, 106) to match the capacitance between the two sections (86, 88) of movable element (86) to provide the same bi-directional actuation capability.