摘要:
A MEMS device (20) includes a proof mass (32) coupled to and surrounding an immovable structure (30). The immovable structure (30) includes fixed fingers (36, 38) extending outwardly from a body (34) of the structure (30). The proof mass (32) includes movable fingers (60), each of which is disposed between a pair (62) of the fixed fingers (36, 38). A central area (42) of the body (34) is coupled to an underlying substrate (24), with the remainder of the immovable structure (30) and the proof mass (32) being suspended above the substrate (24) to largely isolate the MEMS device (20) from package stress, Additionally, the MEMS device (20) includes isolation trenches (80) and interconnects (46, 50, 64) so that the fixed fingers (36), the fixed fingers (38), and the movable fingers (60) are electrically isolated from one another to yield a differential device configuration.
摘要:
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).
摘要:
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).
摘要:
A MEMS device (20) includes a proof mass (32) coupled to and surrounding an immovable structure (30). The immovable structure (30) includes fixed fingers (36, 38) extending outwardly from a body (34) of the structure (30). The proof mass (32) includes movable fingers (60), each of which is disposed between a pair (62) of the fixed fingers (36, 38). A central area (42) of the body (34) is coupled to an underlying substrate (24), with the remainder of the immovable structure (30) and the proof mass (32) being suspended above the substrate (24) to largely isolate the MEMS device (20) from package stress, Additionally, the MEMS device (20) includes isolation trenches (80) and interconnects (46, 50, 64) so that the fixed fingers (36), the fixed fingers (38), and the movable fingers (60) are electrically isolated from one another to yield a differential device configuration.
摘要:
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.
摘要:
An inertial sensor (20) includes a drive mass (30) configured to undergo oscillatory motion and a sense mass (32) linked to the drive mass (30). On-axis torsion springs (58) are coupled to the sense mass (32), the on-axis torsion springs (58) being co-located with an axis of rotation (22). The inertial sensor (20) further includes an off-axis spring system (60). The off-axis spring system (60) includes off-axis springs (68, 70, 72, 74), each having a connection interface (76) coupled to the sense mass (32) at a location on the sense mass (32) that is displaced away from the axis of rotation (22). Together, the on-axis torsion springs (58) and the off-axis spring system (60) enable the sense mass (32) to oscillate out of plane about the axis of rotation (22) at a sense frequency that substantially matches a drive frequency of the drive mass (30).
摘要:
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).
摘要:
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.
摘要:
An inertial sensor (20) includes a drive mass (30) configured to undergo oscillatory motion and a sense mass (32) linked to the drive mass (30). On-axis torsion springs (58) are coupled to the sense mass (32), the on-axis torsion springs (58) being co-located with an axis of rotation (22). The inertial sensor (20) further includes an off-axis spring system (60). The off-axis spring system (60) includes off-axis springs (68, 70, 72, 74), each having a connection interface (76) coupled to the sense mass (32) at a location on the sense mass (32) that is displaced away from the axis of rotation (22). Together, the on-axis torsion springs (58) and the off-axis spring system (60) enable the sense mass (32) to oscillate out of plane about the axis of rotation (22) at a sense frequency that substantially matches a drive frequency of the drive mass (30).
摘要:
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.