Abstract: A sensor with continuous self test is provided. An exemplary inertial sensor may include one or more self test electrodes so that one or more test signals may be applied to the electrodes during normal operation of the sensor. Normal sensor output may be read and stored during normal operation, when self test signals are typically not applied to the sensor. The normal sensor output provides a baseline for comparison to a sensor offset error detection signal produced when a test signal may be applied to one self test electrode, and also to a sense error detection signal when a test signal may be applied to both self test electrodes.

Abstract: A sensor with continuous self test is provided. An exemplary inertial sensor may include one or more self test electrodes so that one or more test signals may be applied to the electrodes during normal operation of the sensor. Normal sensor output may be read and stored during normal operation, when self test signals are typically not applied to the sensor. The normal sensor output provides a baseline for comparison to a sensor offset error detection signal produced when a test signal may be applied to one self test electrode, and also to a sense error detection signal when a test signal may be applied to both self test electrodes.

Abstract: 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.

Abstract: 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.

Abstract: A microelectromechanical systems (MEMS) sensor device (184) includes a sensor portion (180) and a sensor portion (182) that are coupled together to form a vertically integrated configuration having a hermetically sealed chamber (270). The sensor portions (180, 182) can be formed utilizing different micromachining techniques, and are subsequently coupled utilizing a wafer bonding technique to form the sensor device (184). The sensor portion (180) includes one or more sensors (186, 188), and the sensor portion (182) includes one or more sensors (236, 238). The sensors (186, 188) are located inside the chamber (270) facing the sensors (236, 238) also located inside the chamber (270). The sensors (186, 188, 236, 238) are configured to sense different physical stimuli, such as motion, pressure, and magnetic field.

Abstract: Apparatus and methods for applying stress-induced offset compensation and/or scale factor correction in sensor devices are provided. One sensor device (100, 300, 500, 700) includes an integrated circuit device (110, 310, 510, 710), a transducer (120, 320, 520, 720) coupled to the ASIC device, and a stress sensor (130, 330, 530, 730) coupled to the transducer or the integrated circuit device and configured to measure stress on the sensor device independent of the transducer. Another sensor device (900) includes a transducer, a sensor package (940) enclosing the transducer, and a stress sensor (930) coupled to the sensor device package and configured to measure stress on the sensor device independent of the transducer. A method includes detecting, via a stress sensor, an amount of stress being applied to the sensor device and adjusting, via the stress sensor and independent of the transducer, an output of the sensor device by the detected amount of stress.

Abstract: A transducer (20) includes sensors (28, 30) that are bonded to form a vertically integrated configuration. The sensor (28) includes a proof mass (32) movably coupled to and spaced apart from a surface (34) of a substrate (36). The sensor (30) includes a proof mass (58) movably coupled to and spaced apart from a surface (60) of a substrate (56). The substrates (36, 56) are coupled with the surface (60) of substrate (56) facing the surface (34) of substrate (36). Thus, the proof mass (58) faces the proof mass (32). The sensors (28, 30) are fabricated separately and can be formed utilizing differing micromachining techniques. The sensors (28, 30) are subsequently coupled (90) utilizing a wafer bonding technique to form the transducer (20). Embodiments of the transducer (20) may include sensing along one, two, or three orthogonal axes and may be adapted to detect movement at different acceleration sensing ranges.

Abstract: A MEMS device (20) includes a substrate (22), a proof mass (28), and a frame structure (30) laterally spaced apart from the proof mass (28). Compliant members (36) are coupled to the proof mass (28) and the frame structure (30) to retain the proof mass (28) suspended above the surface (26) of the substrate (22) without directly coupling the proof mass (28) to the substrate (22). Anchors (32) suspend the frame structure (30) above the surface (26) of the substrate (22) without directly coupling the structure (30) to the substrate (22), and retain the structure (30) immovable relative to the substrate (22) in a sense direction (42). The compliant members (36) enable movement of the proof mass (28) in the sense direction (42). Movable fingers (38) extending from the proof mass (28) are disposed between fixed fingers (46) extending from the frame structure (30) to form a differential capacitive structure.

Abstract: Apparatus and methods for applying stress-induced offset compensation and/or scale factor correction in sensor devices are provided. One sensor device (100, 300, 500, 700) includes an integrated circuit device (110, 310, 510, 710), a transducer (120, 320, 520, 720) coupled to the ASIC device, and a stress sensor (130, 330, 530, 730) coupled to the transducer or the integrated circuit device and configured to measure stress on the sensor device independent of the transducer. Another sensor device (900) includes a transducer, a sensor package (940) enclosing the transducer, and a stress sensor (930) coupled to the sensor device package and configured to measure stress on the sensor device independent of the transducer. A method includes detecting, via a stress sensor, an amount of stress being applied to the sensor device and adjusting, via the stress sensor and independent of the transducer, an output of the sensor device by the detected amount of stress.

Abstract: A transducer (20) includes sensors (28, 30) that are bonded to form a vertically integrated configuration. The sensor (28) includes a proof mass (32) movably coupled to and spaced apart from a surface (34) of a substrate (36). The sensor (30) includes a proof mass (58) movably coupled to and spaced apart from a surface (60) of a substrate (56). The substrates (36, 56) are coupled with the surface (60) of substrate (56) facing the surface (34) of substrate (36). Thus, the proof mass (58) faces the proof mass (32). The sensors (28, 30) are fabricated separately and can be formed utilizing differing micromachining techniques. The sensors (28, 30) are subsequently coupled (90) utilizing a wafer bonding technique to form the transducer (20). Embodiments of the transducer (20) may include sensing along one, two, or three orthogonal axes and may be adapted to detect movement at different acceleration sensing ranges.

Abstract: A microelectromechanical systems (MEMS) sensor device (184) includes a sensor portion (180) and a sensor portion (182) that are coupled together to form a vertically integrated configuration having a hermetically sealed chamber (270). The sensor portions (180, 182) can be formed utilizing different micromachining techniques, and are subsequently coupled utilizing a wafer bonding technique to form the sensor device (184). The sensor portion (180) includes one or more sensors (186, 188), and the sensor portion (182) includes one or more sensors (236, 238). The sensors (186, 188) are located inside the chamber (270) facing the sensors (236, 238) also located inside the chamber (270). The sensors (186, 188, 236, 238) are configured to sense different physical stimuli, such as motion, pressure, and magnetic field.

Abstract: A transducer package 20 includes a substrate 32 having a first axis of symmetry 36 and a second axis of symmetry 38 arranged orthogonal to the first axis of symmetry 36. At least a first sensor 50 and a second sensor 52 each of which are symmetrically arranged on the substrate 32 relative to one of the first and second axes of symmetry 36 and 38.The first and second sensors 50 and 52 are adapted to detect movement parallel to the other of the first and second axes of symmetry 36 and 38. The first sensor 50 is adapted to detect movement over a first sensing range and the second sensor 52 is adapted to detect movement over a second sensing range, the second sensing range differing from the first sensing range.

Abstract: A sensor with continuous self test (101). An exemplary inertial sensor (106) may include one or more self test electrodes (208, 210) so that one or more test signals (402, 404) may be applied to the electrodes (208, 210) during normal operation of the sensor. Normal sensor output may be read and stored (316) during normal operation, when self test signals are typically not applied to the sensor. The normal sensor output provides a baseline for comparison to a sensor offset error detection signal (408) produced when a test signal may be applied to one self test electrode, and also to a sense error detection signal (406) produced when a test signal may be applied to both self test electrodes (208, 210).

Abstract: An apparatus (100, 200) and method (300) for sensing acceleration are provided. The method includes producing (305) a first signal in response to an acceleration sensed by a transducer, producing (310) a second signal based on the first signal, and actuating (315) the transducer in response to the second signal to remove offset in the transducer. The first signal represents the acceleration, and the second signal represents a low frequency component associated with an offset in the transducer. The apparatus (100) includes a transducer (102) producing a capacitance in response to the acceleration, a sensing system (104, 106, 108) producing a first signal from the capacitance representing the acceleration, and a compensation system (112, 110) coupled between the sensing system and transducer. The compensation system produces a second signal based on the first signal for substantially removing an offset of the transducer.

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 transducer package 20 includes a substrate 32 having a first axis of symmetry 36 and a second axis of symmetry 38 arranged orthogonal to the first axis of symmetry 36. At least a first sensor 50 and a second sensor 52 each of which are symmetrically arranged on the substrate 32 relative to one of the first and second axes of symmetry 36 and 38. The first and second sensors 50 and 52 are adapted to detect movement parallel to the other of the first and second axes of symmetry 36 and 38. The first sensor 50 is adapted to detect movement over a first sensing range and the second sensor 52 is adapted to detect movement over a second sensing range, the second sensing range differing from the first sensing range.

Abstract: An apparatus (100, 200) and method (300) for sensing acceleration are provided. The method includes producing (305) a first signal in response to an acceleration sensed by a transducer, producing (310) a second signal based on the first signal, and actuating (315) the transducer in response to the second signal to remove offset in the transducer. The first signal represents the acceleration, and the second signal represents a low frequency component associated with an offset in the transducer. The apparatus (100) includes a transducer (102) producing a capacitance in response to the acceleration, a sensing system (104, 106, 108) producing a first signal from the capacitance representing the acceleration, and a compensation system (112, 110) coupled between the sensing system and transducer. The compensation system produces a second signal based on the first signal for substantially removing an offset of the transducer.

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: An apparatus and method is disclosed for a semiconductor wafer front side pressure testing system (200, 300, 400). Negative or positive pressure is applied to the top portion of a semiconductor wafer (216, 316) mounted on a support structure or wafer chuck (222, 322, 422). In one embodiment, bellows (232) coupled to the wafer chuck (222, 322, 422) and a platen (218, 318, 418) located above the semiconductor wafer (216, 316) provides a sealed atmosphere above the semiconductor wafer (216, 316) to permit negative or positive pressure to be introduced into this sealed atmosphere. In another embodiment, a seal is provided by a wall portion (421) connected to the chuck (422) contacting a gasket (419) located beneath the platen (418).