[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

USRE45855E1 - Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes - Google Patents

Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes Download PDF

Info

Publication number
USRE45855E1
USRE45855E1 US14/062,671 US201314062671A USRE45855E US RE45855 E1 USRE45855 E1 US RE45855E1 US 201314062671 A US201314062671 A US 201314062671A US RE45855 E USRE45855 E US RE45855E
Authority
US
United States
Prior art keywords
mass
axis
sensing
detection
anchorage
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related, expires
Application number
US14/062,671
Inventor
Luca Coronato
Alessandro Balzelli Ludovico
Sarah Zerbini
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STMicroelectronics SRL
Original Assignee
STMicroelectronics SRL
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by STMicroelectronics SRL filed Critical STMicroelectronics SRL
Priority to US14/062,671 priority Critical patent/USRE45855E1/en
Application granted granted Critical
Publication of USRE45855E1 publication Critical patent/USRE45855E1/en
Expired - Fee Related legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01CMEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C19/00Gyroscopes; Turn-sensitive devices using vibrating masses; Turn-sensitive devices without moving masses; Measuring angular rate using gyroscopic effects
    • G01C19/56Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
    • G01C19/5705Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using masses driven in reciprocating rotary motion about an axis
    • G01C19/5712Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using masses driven in reciprocating rotary motion about an axis the devices involving a micromechanical structure
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/125Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by capacitive pick-up
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/14Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of gyroscopes
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/18Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration in two or more dimensions
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01PMEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P2015/0805Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration
    • G01P2015/0822Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass
    • G01P2015/0825Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass for one single degree of freedom of movement of the mass
    • G01P2015/0828Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values being provided with a particular type of spring-mass-system for defining the displacement of a seismic mass due to an external acceleration for defining out-of-plane movement of the mass for one single degree of freedom of movement of the mass the mass being of the paddle type being suspended at one of its longitudinal ends

Definitions

  • the present invention relates to a microelectromechanical sensor having improved mechanical decoupling of sensing and driving modes.
  • a gyroscope whether uniaxial, biaxial or triaxial
  • an accelerometer whether uniaxial, biaxial or triaxial
  • microprocessing techniques enable formation of microelectromechanical structures or systems (the so-called MEMS) within layers of semiconductor material, which have been deposited (for example, in the case of a layer of polycrystalline silicon) or grown (for example, in the case of an epitaxial layer) on top of sacrificial layers, which are removed by chemical etching.
  • MEMS microelectromechanical structures or systems
  • Inertial sensors, accelerometers and gyroscopes obtained with this technology are encountering an increasing success, for example in the automotive field, in inertial navigation, or in portable devices.
  • Gyroscopes operate according to the theorem of relative accelerations, exploiting Coriolis acceleration.
  • Coriolis force an apparent force, referred to as Coriolis force, which causes a displacement thereof in a direction perpendicular to the direction of the linear velocity and to the axis of rotation.
  • the movable mass is supported via springs that enable a displacement in the direction of the apparent force.
  • the displacement is proportional to the apparent force, and consequently, based on the displacement of the movable mass, it is possible to detect the Coriolis force and the angular velocity that has generated it.
  • the displacement of the movable mass can, for example, be detected capacitively, by measuring, in resonance conditions, the capacitance variations caused by the movement of movable electrodes, integrally fixed to the movable mass and operatively coupled to fixed electrodes.
  • US2007/214883 assigned to STMicroelectronics Srl, discloses a microelectromechanical integrated sensor with a rotary driving motion, which is sensitive to pitch and roll angular velocities.
  • This microelectromechanical sensor includes a single driving mass, anchored to a support at a single central point and driven with rotary motion about an axis, which passes through the central point and is orthogonal to the plane of the driving mass.
  • the rotation of the driving mass enables two mutually orthogonal components of driving velocity in the plane of the mass.
  • At least one through opening is provided inside the driving mass, in which a sensing mass is arranged; the sensing mass is enclosed within the driving mass, suspended with respect to the substrate, and connected to the driving mass via flexible elements.
  • the sensing mass is fixed to the driving mass during its rotary motion, and has a further degree of freedom of movement as a function of an external stress, in particular a Coriolis force acting on the sensor.
  • the flexible elements allow the sensing mass to perform a rotary movement of detection about an axis lying in the plane of the sensor in response to a Coriolis acceleration acting in a direction perpendicular to the plane, in a way substantially decoupled from the driving mass.
  • the microelectromechanical structure in addition to being compact (in so far as it envisages just one driving mass that encloses in its overall dimensions one or more sensing masses), enables with minor structural modifications, a uniaxial, biaxial or triaxial gyroscope (and/or an accelerometer, according to the electrical connections implemented) to be obtained, at the same time ensuring decoupling of the driving mass from the sensing mass during the movement of detection.
  • the microelectromechanical sensor comprises a driving structure formed by a driving mass 3 and by a driving assembly 4 .
  • the driving mass 3 has a circular geometry with radial symmetry, with a substantially planar configuration having a main extension in a plane defined by a first axis x and by a second axis y (referred to in what follows as “plane of the sensor xy”), and negligible dimension, with respect to the main extension, in a direction parallel to a third axis (referred to in what follows as “orthogonal axis z”), forming with the first and second axes x, y a set of three orthogonal axes fixed with respect to the sensor structure.
  • the driving mass 3 has in the plane of the sensor xy substantially the shape of an annulus, and defines at the center a circular empty space 6 , the center O of which coincides with the centroid and the center of symmetry of the driving mass 3 .
  • the driving mass 3 is anchored to a substrate 2 by means of a central anchorage 7 arranged at the center O, to which it is connected through elastic anchorage elements 8 .
  • the elastic anchorage elements 8 depart in a crosswise configuration from the center O along a first axis of symmetry A and a second axis of symmetry B of the driving mass 3 , the axes of symmetry being parallel, respectively, to the first axis x and to the second axis y.
  • the elastic anchorage elements 8 enable a rotary movement of the driving mass 3 about a drive axis passing through the center O, parallel to the orthogonal axis z and perpendicular to the plane of the sensor xy.
  • the driving mass 3 has a first pair of through-openings 9 a, 9 b with a substantially rectangular shape elongated in a direction parallel to the second axis y, aligned in a diametric direction along the first axis of symmetry A, and set on opposite sides with respect to the empty space 6 .
  • the direction of alignment of the through-openings 9 a, 9 b corresponds to a direction of detection of the microelectromechanical sensor 1 (in the case represented in the figure, coinciding with the first axis x).
  • the driving assembly 4 comprises a plurality of driven arms 10 (for example, eight in number), extending externally from the driving mass 3 in a radial direction and spaced apart at a same angular distance, and a plurality of first and second driving arms 12 a, 12 b, extending parallel to, and on opposite sides of, respective driven arms 10 and anchored to the substrate via respective anchorages.
  • Each driven arm 10 carries a plurality of first electrodes 13 , extending in a direction perpendicular to, and on either side of, the driven arm.
  • each of the first and second driving arms 12 a, 12 b carries respective second electrodes 14 a, 14 b, extending towards the respective driven arm 10 and comb-fingered to the corresponding first electrodes 13 .
  • the first driving arms 12 a are all arranged on the same side of the respective driven arms 10 and are all biased at a first voltage.
  • the second driving arms 12 b are all arranged on the opposite side of the respective driven arms 10 , and are all biased at a second voltage.
  • a driving circuit is connected to the second electrodes 14 a, 14 b so as to apply the first and second voltages and determine, by means of mutual and alternating attraction of the electrodes, an oscillatory rotary motion of the driving mass 3 about the drive axis, at a given oscillation frequency.
  • the microelectromechanical sensor 1 further comprises a first pair of acceleration sensors with axis parallel to the orthogonal axis z, and in particular a first pair of first sensing masses 16 a, 16 b, each positioned in a respective one of the through-openings 9 a, 9 b, so as to be completely enclosed and contained within the overall dimensions of the driving mass 3 in the plane of the sensor xy.
  • the first sensing masses 16 a, 16 b have a generally rectangular shape matching the shape of the respective through opening 9 a, 9 b, and are formed by a first rectangular portion 17 , which is wider, and by a second rectangular portion 18 , which is narrower (along the first axis x), connected by a connecting portion 19 , which is shorter (in a direction parallel to the second axis y) than the first and second rectangular portions.
  • Each first sensing mass 16 a, 16 b has a centroid G located within the corresponding first rectangular portion 17 , and is supported by a pair of elastic supporting elements 20 .
  • the elastic supporting elements 20 are connected to the connecting portion 19 , and extend towards the driving mass 3 , in a direction parallel to the second axis y.
  • the elastic supporting elements 20 extend within recesses 21 provided at opposite sides of the sensing masses 16 a, 16 b.
  • the elastic supporting elements 20 extend at a distance from the centroid G of the respective first sensing mass 16 a, 16 b, and form torsional springs that are rigid for the rotary motion of the driving mass 3 , and also enable rotation of the sensing masses about an axis of rotation parallel to the second axis y and lying in the plane of the sensor xy (and, consequently, their movement out of the plane of the sensor xy).
  • a pair of first and second detection electrodes 22 , 23 is arranged underneath the first and second rectangular portions 17 , 18 of each one of the first sensing masses 16 a- 16 b; for example the detection electrodes 22 , 23 are constituted by regions of polycrystalline silicon formed on the substrate 2 , having equal dimensions substantially corresponding to those of the second (and smaller) rectangular portion 18 .
  • the first and second detection electrodes 22 , 23 are separated, respectively from the first and second rectangular portions 17 , 18 , by an air gap, and are connected to a read circuit.
  • the first and second detection electrodes 22 , 23 hence form, together with the first and second rectangular portions 17 , 18 respective detection capacitors.
  • the microelectromechanical sensor 1 is able to operate as a gyroscope, designed to detect an angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x (in FIG. 1 assumed as being counterclockwise), about the first axis x.
  • the rotary movement of the driving mass 3 and of the first sensing masses 16 a- 16 b about the drive axis can be represented by a driving-velocity vector ⁇ right arrow over (v) ⁇ a , tangential to the circumference that describes the driving trajectory.
  • the rotary motion about the first axis x at the angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x determines a force acting on the entire structure, known as Coriolis force (designated by ⁇ right arrow over (F) ⁇ c ).
  • the Coriolis force ⁇ right arrow over (F) ⁇ c is proportional to the vector product between the angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x and the driving velocity ⁇ right arrow over (v) ⁇ a , and is hence directed along the orthogonal axis z, is zero in the points where the driving velocity ⁇ right arrow over (v) ⁇ a is parallel to the first axis x, and, in the points where it does not go to zero, it is directly proportional to the driving velocity ⁇ right arrow over (v) ⁇ a , and consequently it increases with the distance from the center O.
  • the configuration of the elastic anchorage elements 8 is such as to inhibit, at least to a first approximation (see the following discussion), movement of the driving mass 3 out of the plane of the sensor xy, thus allowing decoupling of the motion of detection of the first sensing masses from the driving motion.
  • the displacement of the first sensing masses 16 a, 16 b out of the plane of the sensor xy causes a differential capacitive variation of the detection capacitors, the value of which is proportional to the angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x , which can hence be determined in a per-se known manner via a purposely provided read circuit.
  • the reading scheme is differential
  • the presence of a pair of first sensing masses enables automatic rejection of spurious linear accelerations along the orthogonal axis z.
  • These accelerations in fact, cause a variation in the same direction of the detection capacitors, which is cancelled by the differential reading (on the contrary, the same structure can be operated as an accelerometer for detecting the accelerations along the orthogonal axis z, simply by modifying the electrical connections between the sensing masses and electrodes).
  • the presence of the central anchorage also enables rejection of spurious linear accelerations along the axes x and y, given that the arrangement of elastic anchorage elements 8 is extremely rigid in these directions, and does not enable displacement of the sensing masses.
  • the described structure is able to mechanically reject spurious angular acceleration about the orthogonal axis z, since the frequency response of the sensor can be modeled as a very selective filter.
  • the Applicant has realized that the described microelectromechanical sensor is not optimized, in particular with respect to the decoupling between the driving and sensing modes of operation.
  • the Applicant has realized that flaws in the manufacturing process or improper choices in the structure geometry (e.g. a thickness too small with respect to the dimensions in the plane of the sensor xy, or an improper shape of the elastic elements) may result in the microelectromechanical structure having an improper ratio between the stiffness in the orthogonal direction z and the stiffness in the plane of the sensor xy.
  • the driving mass 3 could have an insufficient stiffness in the orthogonal direction z, so that application of the Coriolis force F c would lead to oscillations movement outside of the plane of the sensor xy not only by the sensing masses (as desired) but also by the same driving mass (contrary to the expected operation). In other words, the decoupling between the driving and sensing movements could be impaired.
  • FIG. 2 shows a situation in which the stiffness of the structure in the orthogonal direction z (provided by the elastic anchorage elements 8 connecting the driving mass 3 to the central anchorage 7 ) is not sufficient to avoid undesired movements of the driving mass 3 outside the plane of the sensor xy, following application of the Coriolis force F c .
  • any non-ideality in the driving arrangement affects also the sensing arrangement, and vice versa.
  • the driving movement is altered, mainly due to the variation in the facing area of the driving electrodes (first electrodes 13 and corresponding second electrodes 14 a, 14 b), because of the movement of the driving mass 3 outside of the plane of the sensor xy.
  • the Coriolis force F c is a function of the tangential driving velocity ⁇ right arrow over (v) ⁇ a , according to the expression:
  • One embodiment of the present invention provides an integrated microelectromechanical structure that allows the aforesaid problems and disadvantages to be overcome, and in particular that has an improved mechanical decoupling between driving and sensing modes.
  • an integrated microelectromechanical structure is consequently provided as defined in the present disclosure.
  • FIG. 1 is a schematic top plan view of a microelectromechanical structure of a known type
  • FIG. 2 is a schematic lateral section of the structure of FIG. 1 , during a sensing operating mode
  • FIG. 3 is a schematic top plan view of a microelectromechanical structure according to one embodiment of the present invention.
  • FIG. 4 is a schematic lateral section of the structure of FIG. 3 , during a sensing operating mode
  • FIG. 5 shows an embodiment of a biaxial sensor
  • FIG. 6 shows an embodiment of a triaxial sensor
  • FIG. 7 shows a block diagram of a sensor device provided with the microelectromechanical structure according to a further embodiment of the invention.
  • One embodiment of the present invention envisages the provision of additional anchorages and elastic anchorage elements connected to the driving mass 3 in order to improve the stiffness of the same driving mass 3 for movements outside the plane of the sensor xy.
  • the microelectromechanical sensor differs from the sensor described with reference to FIG. 1 in that it further comprises a first and a second external anchorage arrangements 30 , 31 , coupled to the driving mass 3 .
  • first and second external anchorage arrangements 30 , 31 are positioned externally of the driving mass 3 , and are coupled to opposite sides of the same driving mass 3 , with respect to the empty space 6 and center O; in the exemplary embodiment shown in FIG. 3 , the first and second external anchorage arrangements 30 , 31 are also aligned along the first axis x, and are diametrically opposite and symmetric with respect to the empty space 6 .
  • Each of the first and second external anchorage arrangements 30 , 31 includes a pair of external anchorages 32 (each one coupled to the substrate 2 , as shown in the following FIG. 4 ) and a pair of external elastic anchorage elements 33 , coupling a respective external anchorage 32 to the driving mass 3 .
  • the external anchorages 32 and external elastic anchorage elements 33 of each pair are arranged on opposite sides of, and symmetrically with respect to, the first axis x.
  • Each one of the external elastic anchorage elements 33 comprises a folded spring, generically extending along the first axis x and having the shape of a “S-shaped” folded beam.
  • each folded spring includes: a first arm A, extending along the first axis x and connected to a respective outer side of the driving mass 3 ; a second arm B extending along the first axis x, parallel to the first arm A, and connected to a respective external anchorage 32 ; an intermediate arm C, also extending along the first axis x, and interposed between the first and second arms A, B in the second direction y; and a first and a second connecting portions D, E, extending along the second axis y and connecting (at a 90° angle) a respective end of the intermediate arm to the first arm A and to the second arm B, respectively.
  • Operation of the microelectromechanical sensor 1 ′ does not differ from the one previously discussed with reference to FIG. 1 , so that an angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x about the first axis x is sensed by the sensor as a function of the displacement of the pair of first sensing masses 16 a, 16 b out of the plane of the sensor xy (caused by the Coriolis Force F c ) and the associated capacitance variation of the detection capacitors.
  • the presence of the additional first and second external anchorage arrangements 30 , 31 improves the overall stiffness of the driving mass 3 and allows to achieve an improved decoupling of the driving and sensing modes, particularly avoiding undesired movements of the driving mass 3 outside of the plane of the sensor xy.
  • first and second external anchorage arrangements 30 , 31 are configured in such a manner that they have a minimum stiffness in the plane of the sensor xy, and they substantially do not influence the driving dynamic in the plane of the sensor xy and in particular they do not alter the driving movement of the driving mass 3 .
  • the folded spring can be subjected to large movements in the plane of the sensor xy, so that they do not influence the linearity of the system.
  • the Applicant has proven that the residual stresses that could be generated due to the presence in the structure of different anchoring points to the substrate 2 are minimized by the disclosed anchorage arrangement (in particular, due to the minimum stiffness in the plane of the sensor xy of the external anchorage elements 30 , 31 , the residual stresses, if present, do not influence the driving dynamic).
  • FIG. 5 shows a biaxial sensor structure according to a further embodiment of the present invention.
  • the microelectromechanical sensor 1 ′ further includes: a second pair of through-openings 9 c, 9 d, which are aligned along the second axis y, are of a substantially rectangular shape elongated in a direction parallel to the first axis x, and are arranged on opposite sides with respect to the empty space 6 ; and a second pair of acceleration sensors with axis parallel to the orthogonal axis z, and in particular a second pair of first sensing masses 16 c, 16 d, housed within the through-openings 9 c, 9 d, and completely enclosed and contained within the driving mass 3 .
  • the first sensing masses 16 c, 16 d are obtained by rotation through 90° of the first sensing masses 16 a, 16 b, and consequently the corresponding elastic supporting elements 20 extend parallel to the first axis x and enable rotation of the respective sensing masses about an axis of rotation parallel to the first axis x.
  • a second pair of first and second detection electrodes 22 , 23 is arranged underneath the first sensing masses 16 c, 16 d, forming therewith respective detection capacitors.
  • the microelectromechanical sensor 1 ′ is also able to detect an angular velocity ⁇ right arrow over ( ⁇ ) ⁇ y about the second axis y.
  • the rotary motion about the second axis y causes a Coriolis force F c , once again directed along the orthogonal axis z, which causes rotation of the first sensing masses 16 c, 16 d about the axis of rotation parallel to the first axis x, and consequent opposite unbalancing of the detection capacitors.
  • a rotation about the first axis x is not sensed by the second pair of first sensing masses 16 c, 16 d, in so far as the resultant Coriolis force ⁇ right arrow over (F) ⁇ c is zero (on account of the fact that the vector product between the angular velocity ⁇ right arrow over ( ⁇ ) ⁇ x and the corresponding driving velocity ⁇ right arrow over (v) ⁇ a is, at least in a first approximation, zero).
  • the rotation about the second axis y is not sensed for similar reasons by the first pair of first sensing masses 16 a, 16 b, and consequently the two axes of detection are not affected and are decoupled from one another.
  • a still different embodiment of the present invention envisages a microelectromechanical structure sensing also angular velocities about the orthogonal axis z (thus operating as a triaxial sensor).
  • the microelectromechanical sensor 1 ′ further comprises a pair of accelerometers with axis lying in the plane of the sensor xy (for example, with their axis lying at an angle of about 45° with respect to the first and second axes x, y), and in particular a pair of second sensing masses 35 a, 35 b set within a third pair of through-openings 36 a, 36 b.
  • the through-openings 36 a, 36 b are rectangular and are aligned in a radial direction (in the example of FIG. 6 , inclined of about 45° with respect to the x and y axes) with their main extension in a direction orthogonal to the radial direction.
  • the second sensing masses 35 a, 35 b have a generally rectangular shape with sides parallel to corresponding sides of the through-openings 36 a, 36 b, are suspended with respect to the substrate 2 , and are connected to the driving mass 3 via second elastic supporting elements 38 .
  • the second elastic supporting elements 38 originate from a point situated approximately at the center of main sides of the second sensing masses 35 a, 35 b, and extend in the first radial direction.
  • the second elastic supporting elements 38 are rigid with respect to the driving motion of the driving mass 3 , and exclusively enable a movement in the radial direction of the respective second sensing masses, while hindering movement in other directions (in other words, they are compliant exclusively in the first radial direction).
  • the second sensing masses 35 a, 35 b have extensions 39 extending from a point situated approximately at the centre of corresponding smaller sides along the direction orthogonal to the first radial direction.
  • the extensions 39 together with fixed electrodes anchored to the substrate, facing the extensions 39 and parallel thereto, form detection capacitors with plane and parallel plates.
  • a respective extension 39 originates, facing and set between two fixed electrodes.
  • first detection electrodes 22 the fixed electrodes arranged in a radially outer position
  • second detection electrodes 23 the fixed electrodes arranged in a radially inner position with respect to the center O.
  • a higher number of electrodes can be provided, comb-fingered to one another.
  • the detection capacitors are in this case in the plane of the sensor xy.
  • the driving mass 3 is rotated about the orthogonal axis z with a driving angular velocity ⁇ right arrow over ( ⁇ ) ⁇ a (for example, counter-clockwise), dragging along with it the second sensing masses 35 a, 35 b.
  • An external angular velocity ⁇ right arrow over ( ⁇ ) ⁇ e to be detected which also acts about the orthogonal axis z, generates a Coriolis force ⁇ right arrow over (F) ⁇ c on the second sensing masses 35 a, 35 b directed in the radial direction (hence directed as a centrifugal force acting on the same masses), causing displacement of the second sensing masses and a capacitive variation of the detection capacitors (as discussed in greater detail in the above application US2007/214883).
  • the second sensing masses 35 a, 35 b can be aligned in any direction of the plane of the sensor xy, the third axis of detection being orthogonal to the plane of the sensor xy and constituting an axis of yaw out of the plane of the sensor xy.
  • FIG. 7 illustrates a sensor device 40 according to a further embodiment and comprising: the microelectromechanical sensor 1 ′; a driving circuit 41 , connected to the driving assembly 4 for imparting the rotary driving motion on the driving mass 3 ; and a read circuit 42 , connected to the detection electrodes 22 , 23 for detecting the displacements of the sensing masses.
  • the read circuit 42 is also configured to switch a mode of operation of the microelectromechanical sensor 1 ′ between a gyroscope mode and an accelerometer mode, by simply modifying the electrical connections between the sensing masses and the electrodes.
  • adding further external anchorages and elastic anchorage elements allows to achieve, when necessary (e.g. when flaws in the manufacturing process occur), an improved decoupling between the driving and sensing modes, and particularly:
  • a correct sizing of the additional external anchorage arrangements assures the linearity of the sensor and does not introduce any further residual stress in the sensor structure.
  • the microelectromechanical sensor has compact dimensions, given the presence of a single driving mass that encloses in its overall dimensions the sensing masses.
  • the rotary motion of the driving mass enables two components of driving velocity, orthogonal to one another in the plane of the sensor, to be automatically obtained, and hence effective implementation of a biaxial detection.
  • a different number and positioning of the external anchorages and elastic anchorage elements may be provided, as well as a different shape and type of the same elastic anchorage elements, different from the folded one (e.g. “L-shaped” elastic elements could equally be used, or other stress-release elastic elements).
  • the driving mass 3 can have a shape different from the circular one, for example any closed polygonal shape. Furthermore, even though this may not be advantageous, said shape may not have a perfect radial symmetry (or in general any other type of symmetry).
  • the displacement of the sensing masses can be detected with a different technique other than the capacitive one, for example, by detecting a magnetic force.
  • the torsional moment for causing the driving mass to oscillate with rotary motion can be generated in a different manner, for example by means of parallel-plate electrodes, or else magnetic actuation.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Gyroscopes (AREA)

Abstract

A driving mass of an integrated microelectromechanical structure is moved with a rotary motion about an axis of rotation, and a sensing mass is connected to the driving mass via elastic supporting elements so as to perform a detection movement in the presence of an external stress. The driving mass is anchored to a first anchorage arranged along the axis of rotation by first elastic anchorage elements. The driving mass is also coupled to a pair of further anchorages positioned externally thereof and coupled to opposite sides with respect to the first anchorage by further elastic anchorage elements; the elastic supporting elements and the first and further elastic anchorage elements render the driving mass fixed to the first sensing mass in the rotary motion, and substantially decoupled from the sensing mass in the detection movement, the detection movement being a rotation about an axis lying in a plane.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
More than one reissue application has been filed for the reissue of U.S. patent application Ser. No. 12/208,980, filed Sep. 11, 2008, which issued as U.S. Pat. No. 8,042,396. The reissue applications are application Ser. No. 14/062,671 (the present application), filed on Oct. 24, 2013 and Ser. No. 14/871,240, filed on Sep. 30, 2015, both of which are reissues of U.S. patent application Ser. No. 12/208,980, filed Sep. 11, 2008.
BACKGROUND
1. Technical Field
The present invention relates to a microelectromechanical sensor having improved mechanical decoupling of sensing and driving modes. In particular, in the following description reference will be made to a gyroscope (whether uniaxial, biaxial or triaxial), which can possibly operate as an accelerometer (whether uniaxial, biaxial or triaxial).
2. Description of the Related Art
As is known, microprocessing techniques enable formation of microelectromechanical structures or systems (the so-called MEMS) within layers of semiconductor material, which have been deposited (for example, in the case of a layer of polycrystalline silicon) or grown (for example, in the case of an epitaxial layer) on top of sacrificial layers, which are removed by chemical etching. Inertial sensors, accelerometers and gyroscopes obtained with this technology are encountering an increasing success, for example in the automotive field, in inertial navigation, or in portable devices.
In particular, integrated semiconductor gyroscopes are known, which are made with MEMS technology. Gyroscopes operate according to the theorem of relative accelerations, exploiting Coriolis acceleration. When an angular velocity is imparted on a movable mass that is moving with a linear velocity, the movable mass “feels” an apparent force, referred to as Coriolis force, which causes a displacement thereof in a direction perpendicular to the direction of the linear velocity and to the axis of rotation. The movable mass is supported via springs that enable a displacement in the direction of the apparent force. According to Hooke's law, the displacement is proportional to the apparent force, and consequently, based on the displacement of the movable mass, it is possible to detect the Coriolis force and the angular velocity that has generated it. The displacement of the movable mass can, for example, be detected capacitively, by measuring, in resonance conditions, the capacitance variations caused by the movement of movable electrodes, integrally fixed to the movable mass and operatively coupled to fixed electrodes.
US2007/214883, assigned to STMicroelectronics Srl, discloses a microelectromechanical integrated sensor with a rotary driving motion, which is sensitive to pitch and roll angular velocities.
This microelectromechanical sensor includes a single driving mass, anchored to a support at a single central point and driven with rotary motion about an axis, which passes through the central point and is orthogonal to the plane of the driving mass. The rotation of the driving mass enables two mutually orthogonal components of driving velocity in the plane of the mass. At least one through opening is provided inside the driving mass, in which a sensing mass is arranged; the sensing mass is enclosed within the driving mass, suspended with respect to the substrate, and connected to the driving mass via flexible elements. The sensing mass is fixed to the driving mass during its rotary motion, and has a further degree of freedom of movement as a function of an external stress, in particular a Coriolis force acting on the sensor. The flexible elements, according to their particular construction, allow the sensing mass to perform a rotary movement of detection about an axis lying in the plane of the sensor in response to a Coriolis acceleration acting in a direction perpendicular to the plane, in a way substantially decoupled from the driving mass. The microelectromechanical structure, in addition to being compact (in so far as it envisages just one driving mass that encloses in its overall dimensions one or more sensing masses), enables with minor structural modifications, a uniaxial, biaxial or triaxial gyroscope (and/or an accelerometer, according to the electrical connections implemented) to be obtained, at the same time ensuring decoupling of the driving mass from the sensing mass during the movement of detection.
In detail, and as shown in FIG. 1, that relates to a uniaxial sensor, the microelectromechanical sensor, denoted with 1, comprises a driving structure formed by a driving mass 3 and by a driving assembly 4. The driving mass 3 has a circular geometry with radial symmetry, with a substantially planar configuration having a main extension in a plane defined by a first axis x and by a second axis y (referred to in what follows as “plane of the sensor xy”), and negligible dimension, with respect to the main extension, in a direction parallel to a third axis (referred to in what follows as “orthogonal axis z”), forming with the first and second axes x, y a set of three orthogonal axes fixed with respect to the sensor structure. In particular, the driving mass 3 has in the plane of the sensor xy substantially the shape of an annulus, and defines at the center a circular empty space 6, the center O of which coincides with the centroid and the center of symmetry of the driving mass 3. The driving mass 3 is anchored to a substrate 2 by means of a central anchorage 7 arranged at the center O, to which it is connected through elastic anchorage elements 8. For example, the elastic anchorage elements 8 depart in a crosswise configuration from the center O along a first axis of symmetry A and a second axis of symmetry B of the driving mass 3, the axes of symmetry being parallel, respectively, to the first axis x and to the second axis y. The elastic anchorage elements 8 enable a rotary movement of the driving mass 3 about a drive axis passing through the center O, parallel to the orthogonal axis z and perpendicular to the plane of the sensor xy.
The driving mass 3 has a first pair of through- openings 9a, 9b with a substantially rectangular shape elongated in a direction parallel to the second axis y, aligned in a diametric direction along the first axis of symmetry A, and set on opposite sides with respect to the empty space 6. In particular, the direction of alignment of the through- openings 9a, 9b corresponds to a direction of detection of the microelectromechanical sensor 1 (in the case represented in the figure, coinciding with the first axis x).
The driving assembly 4 comprises a plurality of driven arms 10 (for example, eight in number), extending externally from the driving mass 3 in a radial direction and spaced apart at a same angular distance, and a plurality of first and second driving arms 12a, 12b, extending parallel to, and on opposite sides of, respective driven arms 10 and anchored to the substrate via respective anchorages. Each driven arm 10 carries a plurality of first electrodes 13, extending in a direction perpendicular to, and on either side of, the driven arm. Furthermore, each of the first and second driving arms 12a, 12b carries respective second electrodes 14a, 14b, extending towards the respective driven arm 10 and comb-fingered to the corresponding first electrodes 13. The first driving arms 12a are all arranged on the same side of the respective driven arms 10 and are all biased at a first voltage. Likewise, the second driving arms 12b are all arranged on the opposite side of the respective driven arms 10, and are all biased at a second voltage. In a per se known manner which is not described in detail, a driving circuit is connected to the second electrodes 14a, 14b so as to apply the first and second voltages and determine, by means of mutual and alternating attraction of the electrodes, an oscillatory rotary motion of the driving mass 3 about the drive axis, at a given oscillation frequency.
The microelectromechanical sensor 1 further comprises a first pair of acceleration sensors with axis parallel to the orthogonal axis z, and in particular a first pair of first sensing masses 16a, 16b, each positioned in a respective one of the through- openings 9a, 9b, so as to be completely enclosed and contained within the overall dimensions of the driving mass 3 in the plane of the sensor xy. The first sensing masses 16a, 16b have a generally rectangular shape matching the shape of the respective through opening 9a, 9b, and are formed by a first rectangular portion 17, which is wider, and by a second rectangular portion 18, which is narrower (along the first axis x), connected by a connecting portion 19, which is shorter (in a direction parallel to the second axis y) than the first and second rectangular portions. Each first sensing mass 16a, 16b has a centroid G located within the corresponding first rectangular portion 17, and is supported by a pair of elastic supporting elements 20. The elastic supporting elements 20 are connected to the connecting portion 19, and extend towards the driving mass 3, in a direction parallel to the second axis y. In other words, the elastic supporting elements 20 extend within recesses 21 provided at opposite sides of the sensing masses 16a, 16b. The elastic supporting elements 20 extend at a distance from the centroid G of the respective first sensing mass 16a, 16b, and form torsional springs that are rigid for the rotary motion of the driving mass 3, and also enable rotation of the sensing masses about an axis of rotation parallel to the second axis y and lying in the plane of the sensor xy (and, consequently, their movement out of the plane of the sensor xy).
A pair of first and second detection electrodes 22, 23 is arranged underneath the first and second rectangular portions 17, 18 of each one of the first sensing masses 16a-16b; for example the detection electrodes 22, 23 are constituted by regions of polycrystalline silicon formed on the substrate 2, having equal dimensions substantially corresponding to those of the second (and smaller) rectangular portion 18. The first and second detection electrodes 22, 23 are separated, respectively from the first and second rectangular portions 17, 18, by an air gap, and are connected to a read circuit. The first and second detection electrodes 22, 23 hence form, together with the first and second rectangular portions 17, 18 respective detection capacitors.
In use, the microelectromechanical sensor 1 is able to operate as a gyroscope, designed to detect an angular velocity {right arrow over (Ω)}x (in FIG. 1 assumed as being counterclockwise), about the first axis x.
On the hypothesis of small displacements of the first sensing masses 16a-16b and of small rotations of the driving mass 3, the rotary movement of the driving mass 3 and of the first sensing masses 16a-16b about the drive axis can be represented by a driving-velocity vector {right arrow over (v)}a, tangential to the circumference that describes the driving trajectory.
In particular, the rotary motion about the first axis x at the angular velocity {right arrow over (Ω)}x determines a force acting on the entire structure, known as Coriolis force (designated by {right arrow over (F)}c). In particular, the Coriolis force {right arrow over (F)}c is proportional to the vector product between the angular velocity {right arrow over (Ω)}x and the driving velocity {right arrow over (v)}a, and is hence directed along the orthogonal axis z, is zero in the points where the driving velocity {right arrow over (v)}a is parallel to the first axis x, and, in the points where it does not go to zero, it is directly proportional to the driving velocity {right arrow over (v)}a, and consequently it increases with the distance from the center O. Over the entire structure, considered as a single rigid body, it is hence possible to identify a distribution of Coriolis forces that vary as the distance from the center O varies. The resultants of the Coriolis forces {right arrow over (F)}c acting on the first sensing masses 16a, 16b at the corresponding centroid G, cause rotation of the sensing masses, which move out of the plane of the sensor xy, about an axis parallel to the second axis y and passing through the first elastic supporting elements 20. This movement is allowed by the torsion of the first elastic supporting elements 20. Instead, the configuration of the elastic anchorage elements 8 is such as to inhibit, at least to a first approximation (see the following discussion), movement of the driving mass 3 out of the plane of the sensor xy, thus allowing decoupling of the motion of detection of the first sensing masses from the driving motion. The displacement of the first sensing masses 16a, 16b out of the plane of the sensor xy causes a differential capacitive variation of the detection capacitors, the value of which is proportional to the angular velocity {right arrow over (Ω)}x, which can hence be determined in a per-se known manner via a purposely provided read circuit. In particular, since the reading scheme is differential, the presence of a pair of first sensing masses enables automatic rejection of spurious linear accelerations along the orthogonal axis z. These accelerations, in fact, cause a variation in the same direction of the detection capacitors, which is cancelled by the differential reading (on the contrary, the same structure can be operated as an accelerometer for detecting the accelerations along the orthogonal axis z, simply by modifying the electrical connections between the sensing masses and electrodes). The presence of the central anchorage also enables rejection of spurious linear accelerations along the axes x and y, given that the arrangement of elastic anchorage elements 8 is extremely rigid in these directions, and does not enable displacement of the sensing masses. Furthermore, the described structure is able to mechanically reject spurious angular acceleration about the orthogonal axis z, since the frequency response of the sensor can be modeled as a very selective filter.
Although it is advantageous with respect to traditional gyroscope structures, the Applicant has realized that the described microelectromechanical sensor is not optimized, in particular with respect to the decoupling between the driving and sensing modes of operation.
In detail, the Applicant has realized that flaws in the manufacturing process or improper choices in the structure geometry (e.g. a thickness too small with respect to the dimensions in the plane of the sensor xy, or an improper shape of the elastic elements) may result in the microelectromechanical structure having an improper ratio between the stiffness in the orthogonal direction z and the stiffness in the plane of the sensor xy. In particular, the driving mass 3 could have an insufficient stiffness in the orthogonal direction z, so that application of the Coriolis force Fc would lead to oscillations movement outside of the plane of the sensor xy not only by the sensing masses (as desired) but also by the same driving mass (contrary to the expected operation). In other words, the decoupling between the driving and sensing movements could be impaired.
FIG. 2 shows a situation in which the stiffness of the structure in the orthogonal direction z (provided by the elastic anchorage elements 8 connecting the driving mass 3 to the central anchorage 7) is not sufficient to avoid undesired movements of the driving mass 3 outside the plane of the sensor xy, following application of the Coriolis force Fc.
The lack of a perfect decoupling between the driving and sensing movements entails a number of disadvantages in the microelectromechanical sensor.
Firstly, any non-ideality in the driving arrangement affects also the sensing arrangement, and vice versa.
Secondly, during sensing operations, the driving movement is altered, mainly due to the variation in the facing area of the driving electrodes (first electrodes 13 and corresponding second electrodes 14a, 14b), because of the movement of the driving mass 3 outside of the plane of the sensor xy. Indeed, the Coriolis force Fc is a function of the tangential driving velocity {right arrow over (v)}a, according to the expression:
F c = 2 · m · Ω -> × v -> a
wherein m is the mass of the sensing mass, {right arrow over (Ω)} is the angular velocity that is to be detected (e.g. the angular velocity {right arrow over (Ω)}x) and {right arrow over (v)}a is the driving velocity at the application point of the Coriolis force Fc. A variation of the driving velocity {right arrow over (v)}a due to a different facing area between the electrodes causes a corresponding variation of the Coriolis force Fc and a variation in the output gain of the sensor. As a result, an undesired variation of the overall sensitivity of the microelectromechanical sensor 1 may occur.
Finally, a structure that is compliant (to a certain degree) outside the plane of the sensor xy is inevitably more affected to shock directed along the orthogonal direction z.
BRIEF SUMMARY
One embodiment of the present invention provides an integrated microelectromechanical structure that allows the aforesaid problems and disadvantages to be overcome, and in particular that has an improved mechanical decoupling between driving and sensing modes.
According to one embodiment of the present invention, an integrated microelectromechanical structure is consequently provided as defined in the present disclosure.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
For a better understanding of the present invention, preferred embodiments thereof are now described purely by way of non-limiting examples and with reference to the attached drawings, wherein:
FIG. 1 is a schematic top plan view of a microelectromechanical structure of a known type;
FIG. 2 is a schematic lateral section of the structure of FIG. 1, during a sensing operating mode;
FIG. 3 is a schematic top plan view of a microelectromechanical structure according to one embodiment of the present invention;
FIG. 4 is a schematic lateral section of the structure of FIG. 3, during a sensing operating mode;
FIG. 5 shows an embodiment of a biaxial sensor;
FIG. 6 shows an embodiment of a triaxial sensor; and
FIG. 7 shows a block diagram of a sensor device provided with the microelectromechanical structure according to a further embodiment of the invention.
DETAILED DESCRIPTION
One embodiment of the present invention envisages the provision of additional anchorages and elastic anchorage elements connected to the driving mass 3 in order to improve the stiffness of the same driving mass 3 for movements outside the plane of the sensor xy.
As shown in FIG. 3 wherein same reference numerals refer to same elements as those in FIG. 1, the microelectromechanical sensor, here denoted with 1′, differs from the sensor described with reference to FIG. 1 in that it further comprises a first and a second external anchorage arrangements 30, 31, coupled to the driving mass 3.
In detail, the first and second external anchorage arrangements 30, 31 are positioned externally of the driving mass 3, and are coupled to opposite sides of the same driving mass 3, with respect to the empty space 6 and center O; in the exemplary embodiment shown in FIG. 3, the first and second external anchorage arrangements 30, 31 are also aligned along the first axis x, and are diametrically opposite and symmetric with respect to the empty space 6.
Each of the first and second external anchorage arrangements 30, 31 includes a pair of external anchorages 32 (each one coupled to the substrate 2, as shown in the following FIG. 4) and a pair of external elastic anchorage elements 33, coupling a respective external anchorage 32 to the driving mass 3. In the exemplary embodiment of FIG. 3, the external anchorages 32 and external elastic anchorage elements 33 of each pair are arranged on opposite sides of, and symmetrically with respect to, the first axis x.
Each one of the external elastic anchorage elements 33 comprises a folded spring, generically extending along the first axis x and having the shape of a “S-shaped” folded beam. In greater detail, each folded spring includes: a first arm A, extending along the first axis x and connected to a respective outer side of the driving mass 3; a second arm B extending along the first axis x, parallel to the first arm A, and connected to a respective external anchorage 32; an intermediate arm C, also extending along the first axis x, and interposed between the first and second arms A, B in the second direction y; and a first and a second connecting portions D, E, extending along the second axis y and connecting (at a 90° angle) a respective end of the intermediate arm to the first arm A and to the second arm B, respectively.
Operation of the microelectromechanical sensor 1′ does not differ from the one previously discussed with reference to FIG. 1, so that an angular velocity {right arrow over (Ω)}x about the first axis x is sensed by the sensor as a function of the displacement of the pair of first sensing masses 16a, 16b out of the plane of the sensor xy (caused by the Coriolis Force Fc) and the associated capacitance variation of the detection capacitors.
However, the presence of the additional first and second external anchorage arrangements 30, 31 improves the overall stiffness of the driving mass 3 and allows to achieve an improved decoupling of the driving and sensing modes, particularly avoiding undesired movements of the driving mass 3 outside of the plane of the sensor xy.
In other words, and as shown in FIG. 4, when the Coriolis force Fc acts on the structure, only the first sensing masses 16a, 16b undergo a rotation outside the plane of the sensor xy, while the movement of the driving mass 3 remains substantially unaltered (and lying in the plane of the sensor xy), so that the sensitivity of the sensor is not affected. Also, it has been proven that undesired vibration modes of the structure, that may arise due to the presence of the additional anchorage elements, are sufficiently removed that they do not interfere with the correct operation of the sensor.
Furthermore, the first and second external anchorage arrangements 30, 31 are configured in such a manner that they have a minimum stiffness in the plane of the sensor xy, and they substantially do not influence the driving dynamic in the plane of the sensor xy and in particular they do not alter the driving movement of the driving mass 3. Indeed, the folded spring can be subjected to large movements in the plane of the sensor xy, so that they do not influence the linearity of the system. Also, the Applicant has proven that the residual stresses that could be generated due to the presence in the structure of different anchoring points to the substrate 2 are minimized by the disclosed anchorage arrangement (in particular, due to the minimum stiffness in the plane of the sensor xy of the external anchorage elements 30, 31, the residual stresses, if present, do not influence the driving dynamic).
FIG. 5 shows a biaxial sensor structure according to a further embodiment of the present invention.
The microelectromechanical sensor 1′ further includes: a second pair of through- openings 9c, 9d, which are aligned along the second axis y, are of a substantially rectangular shape elongated in a direction parallel to the first axis x, and are arranged on opposite sides with respect to the empty space 6; and a second pair of acceleration sensors with axis parallel to the orthogonal axis z, and in particular a second pair of first sensing masses 16c, 16d, housed within the through- openings 9c, 9d, and completely enclosed and contained within the driving mass 3. The first sensing masses 16c, 16d are obtained by rotation through 90° of the first sensing masses 16a, 16b, and consequently the corresponding elastic supporting elements 20 extend parallel to the first axis x and enable rotation of the respective sensing masses about an axis of rotation parallel to the first axis x. A second pair of first and second detection electrodes 22, 23 is arranged underneath the first sensing masses 16c, 16d, forming therewith respective detection capacitors. In use, the microelectromechanical sensor 1′ is also able to detect an angular velocity {right arrow over (Ω)}y about the second axis y. The rotary motion about the second axis y causes a Coriolis force Fc, once again directed along the orthogonal axis z, which causes rotation of the first sensing masses 16c, 16d about the axis of rotation parallel to the first axis x, and consequent opposite unbalancing of the detection capacitors. In particular, a rotation about the first axis x is not sensed by the second pair of first sensing masses 16c, 16d, in so far as the resultant Coriolis force {right arrow over (F)}c is zero (on account of the fact that the vector product between the angular velocity {right arrow over (Ω)}x and the corresponding driving velocity {right arrow over (v)}a is, at least in a first approximation, zero). Likewise, the rotation about the second axis y is not sensed for similar reasons by the first pair of first sensing masses 16a, 16b, and consequently the two axes of detection are not affected and are decoupled from one another.
A still different embodiment of the present invention envisages a microelectromechanical structure sensing also angular velocities about the orthogonal axis z (thus operating as a triaxial sensor).
In detail (see FIG. 6), the microelectromechanical sensor 1′ further comprises a pair of accelerometers with axis lying in the plane of the sensor xy (for example, with their axis lying at an angle of about 45° with respect to the first and second axes x, y), and in particular a pair of second sensing masses 35a, 35b set within a third pair of through- openings 36a, 36b. The through- openings 36a, 36b are rectangular and are aligned in a radial direction (in the example of FIG. 6, inclined of about 45° with respect to the x and y axes) with their main extension in a direction orthogonal to the radial direction. The second sensing masses 35a, 35b have a generally rectangular shape with sides parallel to corresponding sides of the through- openings 36a, 36b, are suspended with respect to the substrate 2, and are connected to the driving mass 3 via second elastic supporting elements 38. The second elastic supporting elements 38 originate from a point situated approximately at the center of main sides of the second sensing masses 35a, 35b, and extend in the first radial direction. In particular, the second elastic supporting elements 38 are rigid with respect to the driving motion of the driving mass 3, and exclusively enable a movement in the radial direction of the respective second sensing masses, while hindering movement in other directions (in other words, they are compliant exclusively in the first radial direction). Furthermore, the second sensing masses 35a, 35b have extensions 39 extending from a point situated approximately at the centre of corresponding smaller sides along the direction orthogonal to the first radial direction. The extensions 39, together with fixed electrodes anchored to the substrate, facing the extensions 39 and parallel thereto, form detection capacitors with plane and parallel plates. For example, from each smaller side of each second sensing mass 35a, 35b a respective extension 39 originates, facing and set between two fixed electrodes. In a way similar to what has been previously described, it is possible to denote, as first detection electrodes 22, the fixed electrodes arranged in a radially outer position, and as second detection electrodes 23 the fixed electrodes arranged in a radially inner position with respect to the center O. Alternatively, a higher number of electrodes can be provided, comb-fingered to one another. In any event, the detection capacitors are in this case in the plane of the sensor xy.
In use, the driving mass 3 is rotated about the orthogonal axis z with a driving angular velocity {right arrow over (Ω)}a (for example, counter-clockwise), dragging along with it the second sensing masses 35a, 35b. An external angular velocity {right arrow over (Ω)}e to be detected, which also acts about the orthogonal axis z, generates a Coriolis force {right arrow over (F)}c on the second sensing masses 35a, 35b directed in the radial direction (hence directed as a centrifugal force acting on the same masses), causing displacement of the second sensing masses and a capacitive variation of the detection capacitors (as discussed in greater detail in the above application US2007/214883).
It is evident that the second sensing masses 35a, 35b can be aligned in any direction of the plane of the sensor xy, the third axis of detection being orthogonal to the plane of the sensor xy and constituting an axis of yaw out of the plane of the sensor xy.
FIG. 7 illustrates a sensor device 40 according to a further embodiment and comprising: the microelectromechanical sensor 1′; a driving circuit 41, connected to the driving assembly 4 for imparting the rotary driving motion on the driving mass 3; and a read circuit 42, connected to the detection electrodes 22, 23 for detecting the displacements of the sensing masses. The read circuit 42 is also configured to switch a mode of operation of the microelectromechanical sensor 1′ between a gyroscope mode and an accelerometer mode, by simply modifying the electrical connections between the sensing masses and the electrodes.
The advantages of the microelectromechanical sensor are clear from the foregoing description.
In particular, adding further external anchorages and elastic anchorage elements (particularly of the folded type) allows to achieve, when necessary (e.g. when flaws in the manufacturing process occur), an improved decoupling between the driving and sensing modes, and particularly:
    • a reduced interference of the driving arrangement on the sensing arrangement;
    • a farther separation of the undesired vibration modes away from the operating frequency range;
    • an improved control of the sensitivity; and
    • an improved resistance to external shocks.
The use of folded springs for the external elastic anchorage elements allows a greater displacement of the driving mass 3 in the plane of the sensor xy (compared to other type of springs), and minimizes possible disturbance effects on the linearity of the system.
A correct sizing of the additional external anchorage arrangements assures the linearity of the sensor and does not introduce any further residual stress in the sensor structure.
Moreover, the microelectromechanical sensor has compact dimensions, given the presence of a single driving mass that encloses in its overall dimensions the sensing masses. The rotary motion of the driving mass enables two components of driving velocity, orthogonal to one another in the plane of the sensor, to be automatically obtained, and hence effective implementation of a biaxial detection.
Finally, it is clear that modifications and variations can be made to what is described and illustrated herein, without thereby departing from the scope of the present invention.
In particular, a different number and positioning of the external anchorages and elastic anchorage elements may be provided, as well as a different shape and type of the same elastic anchorage elements, different from the folded one (e.g. “L-shaped” elastic elements could equally be used, or other stress-release elastic elements).
The driving mass 3 can have a shape different from the circular one, for example any closed polygonal shape. Furthermore, even though this may not be advantageous, said shape may not have a perfect radial symmetry (or in general any other type of symmetry).
In a per-se known manner, the displacement of the sensing masses can be detected with a different technique other than the capacitive one, for example, by detecting a magnetic force.
Furthermore, the torsional moment for causing the driving mass to oscillate with rotary motion can be generated in a different manner, for example by means of parallel-plate electrodes, or else magnetic actuation.
The various embodiments described above can be combined to provide further embodiments. All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments.
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.

Claims (24)

The invention claimed is:
1. An integrated microelectromechanical structure, comprising:
a substrate;
a driving mass designed to be moved with a rotary motion about an axis of rotation and having a central aperture relative to a central axis;
a first anchorage arrangement positioned in the central aperture and structured to anchor the driving mass to the substrate; arranged at the central axis and coupled to the substrate;
a first opening provided within said driving mass;
elastic anchorage elements coupling the driving mass to the first anchorage;
a first sensing mass of a first type arranged inside said first opening;
first elastic supporting elements connecting coupling said first sensing mass to said driving mass and configured to enable the first sensing mass to move in a first direction in response to a first acceleration to perform a first detection movementin the presence of a first external stress;
a second sensing mass that is of a type that is different from the first sensing mass;
second elastic supporting elements coupled between the driving mass and the second sensing mass and configured to enable the second sensing mass to perform a second detection movement in response to a second acceleration, said first detection movement being a rotational movement about a first axis lying in a plane of said driving mass, and said second detection movement being a linear movement along a second axis lying in said plane;
a second anchorage arrangement positioned externally of said driving mass and coupled to a first side of the driving mass;
a third anchorage arrangement positioned externally of said driving mass and coupled to a second side of the driving mass, the second side being opposite to the first side;
wherein said first elastic supporting elements and said first, second and third anchorage arrangements anchorages are so configured so that said driving first sensing mass is fixed to said first sensing driving mass of the first type in said rotary motion and driven relative to the central axis, and the first sensing mass is decoupled therefrom in said detection movement from the driving mass when moving in said first direction.
2. The structure according to claim 1, wherein said driving mass has an annular shape extending substantially in a plane, and said central axis of rotation is perpendicular to said plane, and said first anchorage arrangement includes: a central anchorage arranged substantially at a center of said driving mass in the central aperture defined by said annular shape, and central elastic anchorage elements coupling said central anchorage to said driving mass, extending in said central aperture; and wherein said second side is opposite to said first side of the driving mass with respect to said central aperture axis.
3. The structure according to claim 2 1, wherein said second and third anchorage arrangements anchorages are diametrically opposite and symmetric with respect to said central aperture axis.
4. The structure according to claim 1, wherein each of said second and third anchorage arrangements anchorages comprises an external anchorage member coupled to the substrate, and an external elastic anchorage element coupling said external anchorage to said driving mass, extending outside said driving mass.
5. The structure according to claim 4, wherein said external elastic anchorage element comprises a folded spring.
6. The structure according to claim 1, wherein each of said second and third anchorage arrangements anchorages comprises a pair of external anchorages members coupled to the substrate, and a pair of folded springs connecting a respective one of said external anchorages members to said driving mass.
7. The structure according to claim 1, wherein said external stress first acceleration is generated by a Coriolis force acting in a direction perpendicular to a plane of said driving mass, and said first detection movement is a rotation outside said plane about an axis defined by said first elastic supporting elements.
8. The structure according to claim 1, wherein said driving mass extends substantially in a plane and the structure further comprises:
a second sensing mass of the first type, which that is aligned with said first sensing mass of the first type along a first axis of detection lying in said plane and is arranged in a second opening provided within said driving mass, said first and second sensing masses of the first type being enclosed in overall dimensions located inward of said driving mass in said plane; and
detection means associated with each of said first and second sensing masses of the first type for detecting said a first detection movement, said first detection movement being a rotational movement about an axis lying in said plane and perpendicular to said first axis of detection.
9. The structure according to claim 8, wherein said detection means are configured to implement a differential detection scheme.
10. The structure according to claim 8, wherein said detection means include detection electrodes which are set facing said first and second sensing masses of the first type.
11. The structure according to claim 1, further comprising:
a second sensing mass of the first type, forming with said first sensing mass of the first type a first pair of sensing masses of the first type aligned along a first axis of detection lying in a plane on opposite sides with respect to said first anchorage arrangement; and
a second pair of sensing masses of the first type aligned along a second axis of detection lying in said plane and orthogonal to said first axis of detection, on opposite sides of said first anchorage arrangement.
12. The structure according to claim 1, further comprising:
a sensing mass of a second type arranged inside a second opening provided within said driving mass; and
second elastic supporting elements coupled between the driving mass and the sensing mass of the second type and configured to enable the sensing mass of the second type to perform a second detection movement in a presence of a second external stress, said first detection movement being a rotational movement about a first axis lying in a plane of said driving mass, and said second detection movement being a linear movement along a second axis lying in said plane.
13. The structure according to claim 12 1, wherein said second external stress is acceleration is generated by a Coriolis force acting in a radial direction, and said linear movement is directed along said radial direction.
14. The structure according to claim 12 1, defining a triaxial gyroscope, further including:
a second third sensing mass of the first type, forming with said first sensing mass of the first type a first pair of sensing masses of the first type aligned along a first axis of detection lying in a plane on opposite sides with respect to said first anchorage arrangement; and
a second pair of sensing masses of the first type aligned along a second axis of detection lying in said plane and orthogonal to said first axis of detection, on opposite sides of said first anchorage arrangement,
wherein said first and second pairs of sensing masses of the first type are configured to detect, respectively, a first external angular velocity and a second external angular velocity about said first and second axis of detection, and said second sensing mass of the second type is configured to detect a third external angular velocity about a third axis of detection orthogonal to said plane.
15. A sensor device comprising:
a microelectromechanical structure including:
a driving mass designed to be moved with a rotary motion about an axis of rotation;
a first anchorage positioned along said axis of rotation;
first elastic anchorage elements anchoring said driving mass to said first anchorage;
a first opening provided within said driving mass;
a first sensing mass arranged inside said first opening;
first elastic supporting elements connecting said first sensing mass to said driving mass and configured to enable said first sensing mass to perform a first detection movement in the presence of an external stress;
a second anchorage positioned externally of said driving mass; and
a second elastic anchorage element coupling an external side of the driving mass to said second anchorage;
wherein said first elastic supporting elements and said first and second elastic anchorage elements are so configured that said first sensing mass is fixed to said driving mass in said rotary motion, and is substantially decoupled from said driving mass in said detection movement.
16. The sensor device according to claim 15, further comprising a read stage configured to switch a mode of operation of said microelectromechanical structure between a gyroscope mode and an accelerometer mode.
17. The sensor device of claim 15, wherein the second elastic anchorage element couples a first side of the driving mass to said second anchorage, the sensor device further comprising:
a third anchorage positioned externally of said driving mass; and
a third elastic anchorage element coupling a second side of the driving mass to said third anchorage.
18. The sensor device according to claim 15, wherein the first sensing mass is of a first type, the microelectromechanical structure further comprising:
a sensing mass of a second type arranged inside a second opening provided within said driving mass; and
second elastic supporting elements coupled between the driving mass and the sensing mass of the second type and configured to enable the sensing mass of the second type to perform a second detection movement in a presence of a second external stress, said first detection movement being a rotational movement about a first axis, and said second detection movement being a linear movement along a second axis.
19. The sensor device according to claim 18, defining a triaxial gyroscope, the microelectromechanical structure further including:
a second sensing mass of the first type, forming with said first sensing mass of the first type a first pair of sensing masses of the first type aligned along a first axis of detection on opposite sides with respect to said first anchorage; and
a second pair of sensing masses of the first type aligned along a second axis of detection orthogonal to said first axis of detection, on opposite sides of said first anchorage,
wherein said first and second pairs of sensing masses of the first type are configured to detect, respectively, a first external angular velocity and a second external angular velocity about said first and second axis of detection, and said sensing mass of the second type is configured to detect a third external angular velocity about a third axis of detection orthogonal to first and second axes of detection.
20. A microelectromechanical device comprising:
a first anchorage;
first elastic anchorage elements;
a driving mass operable to move in a rotary motion about an axis of rotation, the driving mass being anchored via the first elastic anchorage elements to the first anchorage positioned along the axis of rotation and the driving mass substantially extending in a plane perpendicular to the axis of rotation;
a first opening disposed positioned within the driving mass;
first elastic supporting elements;
a first sensing mass of a first type disposed positioned within the first opening and having side surfaces enclosed by said driving mass, the first sensing mass being coupled to the driving mass via the first elastic supporting elements, the first elastic supporting elements being configured to allow for a first detection movement in response to a first external stress, the first detection movement being a rotational movement outside the plane about an axis lying in the plane;
a pair of further second anchorages positioned externally of the driving mass;
furthersecond elastic anchorage elements coupling, each of the second elastic anchorage elements being coupled between one of the furthersecond anchorages to oppositeand external sides of said driving mass;
the first elastic supporting elements and the first and further elastic anchorage elements being configured to fix the first sensing mass to the driving mass during said rotary motion, and wherein the first and further elastic anchorage elements are being configured to prevent said driving mass from undergoing said rotational movement outside the plane in response to said first external stress.
21. The device according to claim 20, further comprising:
a second sensing mass of the first type, which is aligned with said first sensing mass of the first type along a first axis of detection lying in said plane and is arranged in a second opening provided within said driving mass, said first and second sensing masses of the first type being enclosed in overall dimensions of said driving mass in said plane; and
detection means associated with each of said first and second sensing masses of the first type for detecting said first detection movement, said first detection movement being a rotational movement about an axis lying in said plane and perpendicular to said first axis of detection.
22. The device according to claim 20, further comprising a second sensing mass of a second type arranged inside a second opening provided within said driving mass and connected coupled to said driving mass via second elastic supporting elements in such a manner so as to perform a second detection movement in a presence of a second external stress, said first detection movement being a rotational movement about a first axis lying in said plane, and said second detection movement being a linear movement along a second axis lying in said plane.
23. The device according to claim 22, wherein said second external stress is a Coriolis force acting in a radial direction, and said linear movement is directed along said radial direction.
24. The device according to claim 22, defining a triaxial gyroscope, further including:
a second third sensing mass of the first type, forming with said first sensing mass of the first type a first pair of sensing masses of the first type aligned along a first axis of detection lying in a plane on opposite first and second sides with respect to said first anchorage; and
a second pair of sensing masses of the first type aligned along a second axis of detection lying in said plane and orthogonal to said first axis of detection, on opposite third and fourth sides of said first anchorage,
wherein said first and second pairs of sensing masses of the first type are configured to detect, respectively, a first external angular velocity and a second external angular velocity about said first and second axes of detection, and said second sensing mass of the second type is configured to detect a third external angular velocity about a third axis of detection orthogonal to said plane.
US14/062,671 2007-09-11 2013-10-24 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes Expired - Fee Related USRE45855E1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US14/062,671 USRE45855E1 (en) 2007-09-11 2013-10-24 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US97149607P 2007-09-11 2007-09-11
US12/208,980 US8042396B2 (en) 2007-09-11 2008-09-11 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
US14/062,671 USRE45855E1 (en) 2007-09-11 2013-10-24 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US12/208,980 Reissue US8042396B2 (en) 2007-09-11 2008-09-11 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes

Publications (1)

Publication Number Publication Date
USRE45855E1 true USRE45855E1 (en) 2016-01-19

Family

ID=40430422

Family Applications (4)

Application Number Title Priority Date Filing Date
US12/208,977 Ceased US8042394B2 (en) 2007-09-11 2008-09-11 High sensitivity microelectromechanical sensor with rotary driving motion
US12/208,980 Ceased US8042396B2 (en) 2007-09-11 2008-09-11 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
US14/062,671 Expired - Fee Related USRE45855E1 (en) 2007-09-11 2013-10-24 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
US14/062,687 Active 2030-06-04 USRE45792E1 (en) 2007-09-11 2013-10-24 High sensitivity microelectromechanical sensor with driving motion

Family Applications Before (2)

Application Number Title Priority Date Filing Date
US12/208,977 Ceased US8042394B2 (en) 2007-09-11 2008-09-11 High sensitivity microelectromechanical sensor with rotary driving motion
US12/208,980 Ceased US8042396B2 (en) 2007-09-11 2008-09-11 Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes

Family Applications After (1)

Application Number Title Priority Date Filing Date
US14/062,687 Active 2030-06-04 USRE45792E1 (en) 2007-09-11 2013-10-24 High sensitivity microelectromechanical sensor with driving motion

Country Status (1)

Country Link
US (4) US8042394B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150168437A1 (en) * 2012-05-29 2015-06-18 Denso Corporation Physical quantity sensor
US20170285061A1 (en) * 2016-03-31 2017-10-05 Stmicroelectronics S.R.L. Accelerometric sensor in mems technology having high accuracy and low sensitivity to temperature and ageing
US12050102B2 (en) 2019-09-30 2024-07-30 Stmicroelectronics S.R.L. Waterproof MEMS button device, input device comprising the MEMS button device and electronic apparatus

Families Citing this family (93)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1832841B1 (en) * 2006-03-10 2015-12-30 STMicroelectronics Srl Microelectromechanical integrated sensor structure with rotary driving motion
US8042394B2 (en) 2007-09-11 2011-10-25 Stmicroelectronics S.R.L. High sensitivity microelectromechanical sensor with rotary driving motion
US8082788B1 (en) * 2007-12-20 2011-12-27 Advanced Numicro Systems, Inc. MEMS load cell and strain sensor
ITTO20090489A1 (en) * 2008-11-26 2010-12-27 St Microelectronics Srl READING CIRCUIT FOR A MULTI-AXIS MEMS GYROSCOPE WITH DETECTED DETECTION DIRECTIONS COMPARED TO THE REFERENCE AXES, AND CORRESPONDING MEMS MULTI-AXIS GIROSCOPE
IT1391973B1 (en) 2008-11-26 2012-02-02 St Microelectronics Rousset MONO OR BIASSIAL MICROELECTROMECHANICAL GYROSCOPE WITH INCREASED SENSITIVITY TO THE ANGULAR SPEED DETECTION
IT1391972B1 (en) 2008-11-26 2012-02-02 St Microelectronics Rousset MICROELETTROMECHANICAL GYROSCOPE WITH ROTARY DRIVE MOVEMENT AND IMPROVED ELECTRICAL CHARACTERISTICS
IT1392741B1 (en) 2008-12-23 2012-03-16 St Microelectronics Rousset MICROELETTROMECHANICAL GYROSCOPE WITH IMPROVED REJECTION OF ACCELERATION DISORDERS
IT1394007B1 (en) 2009-05-11 2012-05-17 St Microelectronics Rousset MICROELETTROMECANICAL STRUCTURE WITH IMPROVED REJECTION OF ACCELERATION DISORDERS
DE102009027897B4 (en) 2009-07-21 2023-07-20 Robert Bosch Gmbh Micromechanical rotation rate sensor
US8739626B2 (en) * 2009-08-04 2014-06-03 Fairchild Semiconductor Corporation Micromachined inertial sensor devices
KR101700124B1 (en) 2009-08-04 2017-02-13 페어차일드 세미컨덕터 코포레이션 Micromachined inertial sensor devices
US9097524B2 (en) 2009-09-11 2015-08-04 Invensense, Inc. MEMS device with improved spring system
US8534127B2 (en) 2009-09-11 2013-09-17 Invensense, Inc. Extension-mode angular velocity sensor
WO2011073935A2 (en) * 2009-12-16 2011-06-23 Y-Sensors Ltd. Tethered, levitated-mass accelerometer
ITTO20091042A1 (en) 2009-12-24 2011-06-25 St Microelectronics Srl MICROELETTROMECHANICAL INTEGRATED GYROSCOPE WITH IMPROVED DRIVE STRUCTURE
CN103221331B (en) 2010-09-18 2016-02-03 快捷半导体公司 Hermetically sealed for MEMS
EP2616389B1 (en) 2010-09-18 2017-04-05 Fairchild Semiconductor Corporation Multi-die mems package
KR101443730B1 (en) 2010-09-18 2014-09-23 페어차일드 세미컨덕터 코포레이션 A microelectromechanical die, and a method for making a low-quadrature-error suspension
WO2012037538A2 (en) * 2010-09-18 2012-03-22 Fairchild Semiconductor Corporation Micromachined monolithic 6-axis inertial sensor
US9455354B2 (en) 2010-09-18 2016-09-27 Fairchild Semiconductor Corporation Micromachined 3-axis accelerometer with a single proof-mass
US8813564B2 (en) 2010-09-18 2014-08-26 Fairchild Semiconductor Corporation MEMS multi-axis gyroscope with central suspension and gimbal structure
US10065851B2 (en) 2010-09-20 2018-09-04 Fairchild Semiconductor Corporation Microelectromechanical pressure sensor including reference capacitor
CN103209922B (en) 2010-09-20 2014-09-17 快捷半导体公司 Through silicon via with reduced shunt capacitance
JP2012173055A (en) 2011-02-18 2012-09-10 Seiko Epson Corp Physical quantity sensor and electronic apparatus
US9354061B2 (en) * 2011-03-31 2016-05-31 Ramot At Tel Aviv University Ltd. Compliant structures with time-varying moment of inertia
ITTO20110806A1 (en) 2011-09-12 2013-03-13 St Microelectronics Srl MICROELETTROMECANICAL DEVICE INTEGRATING A GYROSCOPE AND AN ACCELEROMETER
US9863769B2 (en) 2011-09-16 2018-01-09 Invensense, Inc. MEMS sensor with decoupled drive system
US8833162B2 (en) * 2011-09-16 2014-09-16 Invensense, Inc. Micromachined gyroscope including a guided mass system
US9714842B2 (en) * 2011-09-16 2017-07-25 Invensense, Inc. Gyroscope self test by applying rotation on coriolis sense mass
US9170107B2 (en) * 2011-09-16 2015-10-27 Invensense, Inc. Micromachined gyroscope including a guided mass system
US10914584B2 (en) 2011-09-16 2021-02-09 Invensense, Inc. Drive and sense balanced, semi-coupled 3-axis gyroscope
US8448513B2 (en) 2011-10-05 2013-05-28 Freescale Semiconductor, Inc. Rotary disk gyroscope
US8739627B2 (en) * 2011-10-26 2014-06-03 Freescale Semiconductor, Inc. Inertial sensor with off-axis spring system
DE102011057081A1 (en) * 2011-12-28 2013-07-04 Maxim Integrated Products, Inc. Micro rotation rate sensor and method for operating a micro yaw rate sensor
US9062972B2 (en) 2012-01-31 2015-06-23 Fairchild Semiconductor Corporation MEMS multi-axis accelerometer electrode structure
US8978475B2 (en) 2012-02-01 2015-03-17 Fairchild Semiconductor Corporation MEMS proof mass with split z-axis portions
US8754694B2 (en) 2012-04-03 2014-06-17 Fairchild Semiconductor Corporation Accurate ninety-degree phase shifter
JP6338813B2 (en) 2012-04-03 2018-06-06 セイコーエプソン株式会社 Gyro sensor and electronic device using the same
US8742964B2 (en) 2012-04-04 2014-06-03 Fairchild Semiconductor Corporation Noise reduction method with chopping for a merged MEMS accelerometer sensor
US9488693B2 (en) 2012-04-04 2016-11-08 Fairchild Semiconductor Corporation Self test of MEMS accelerometer with ASICS integrated capacitors
KR102058489B1 (en) 2012-04-05 2019-12-23 페어차일드 세미컨덕터 코포레이션 Mems device front-end charge amplifier
EP2647952B1 (en) 2012-04-05 2017-11-15 Fairchild Semiconductor Corporation Mems device automatic-gain control loop for mechanical amplitude drive
EP2647955B8 (en) 2012-04-05 2018-12-19 Fairchild Semiconductor Corporation MEMS device quadrature phase shift cancellation
US9069006B2 (en) 2012-04-05 2015-06-30 Fairchild Semiconductor Corporation Self test of MEMS gyroscope with ASICs integrated capacitors
US9625272B2 (en) 2012-04-12 2017-04-18 Fairchild Semiconductor Corporation MEMS quadrature cancellation and signal demodulation
US9094027B2 (en) 2012-04-12 2015-07-28 Fairchild Semiconductor Corporation Micro-electro-mechanical-system (MEMS) driver
JP6098780B2 (en) 2012-04-19 2017-03-22 セイコーエプソン株式会社 Gyro sensor and electronics
CN104541130B (en) * 2012-06-22 2017-05-10 独立行政法人产业技术综合研究所 Device for measuring rotation angle acceleration
DE102013014881B4 (en) 2012-09-12 2023-05-04 Fairchild Semiconductor Corporation Enhanced silicon via with multi-material fill
US9547095B2 (en) 2012-12-19 2017-01-17 Westerngeco L.L.C. MEMS-based rotation sensor for seismic applications and sensor units having same
EP2775258B1 (en) * 2013-03-05 2016-02-03 Teknologian tutkimuskeskus VTT Oy Microelectromechanical gyroscope
US9194704B2 (en) * 2013-03-13 2015-11-24 Freescale Semiconductor, Inc. Angular rate sensor having multiple axis sensing capability
WO2015042700A1 (en) 2013-09-24 2015-04-02 Motion Engine Inc. Mems components and method of wafer-level manufacturing thereof
JP6339669B2 (en) 2013-07-08 2018-06-06 モーション・エンジン・インコーポレーテッド MEMS device and method of manufacturing
EP3028007A4 (en) 2013-08-02 2017-07-12 Motion Engine Inc. Mems motion sensor and method of manufacturing
US9404747B2 (en) 2013-10-30 2016-08-02 Stmicroelectroncs S.R.L. Microelectromechanical gyroscope with compensation of quadrature error drift
JP6590812B2 (en) 2014-01-09 2019-10-16 モーション・エンジン・インコーポレーテッド Integrated MEMS system
US9958271B2 (en) 2014-01-21 2018-05-01 Invensense, Inc. Configuration to reduce non-linear motion
US20170030788A1 (en) 2014-04-10 2017-02-02 Motion Engine Inc. Mems pressure sensor
CN105043370B (en) * 2014-04-29 2019-01-22 财团法人工业技术研究院 Micro-motor device with fulcrum element
US11674803B2 (en) 2014-06-02 2023-06-13 Motion Engine, Inc. Multi-mass MEMS motion sensor
US9645166B2 (en) 2014-06-26 2017-05-09 Lumedyne Technologies Incorporated Systems and methods for controlling oscillation of a gyroscope
US9551730B2 (en) * 2014-07-02 2017-01-24 Merlin Technology, Inc. Mechanical shock resistant MEMS accelerometer arrangement, associated method, apparatus and system
US10969399B1 (en) 2014-07-17 2021-04-06 Merlin Technology, Inc. Advanced mechanical shock resistance for an accelerometer in an inground device and associated methods
US10038443B2 (en) * 2014-10-20 2018-07-31 Ford Global Technologies, Llc Directional proximity switch assembly
CA3004760A1 (en) 2014-12-09 2016-06-16 Motion Engine Inc. 3d mems magnetometer and associated methods
US10407299B2 (en) 2015-01-15 2019-09-10 Motion Engine Inc. 3D MEMS device with hermetic cavity
US9952252B2 (en) * 2015-05-15 2018-04-24 Invensense, Inc. Offset rejection electrodes
US10295558B2 (en) 2015-05-15 2019-05-21 Invensense, Inc. Offset rejection electrodes
US11231441B2 (en) 2015-05-15 2022-01-25 Invensense, Inc. MEMS structure for offset minimization of out-of-plane sensing accelerometers
TWI650558B (en) 2015-05-20 2019-02-11 美商路梅戴尼科技公司 Method and system for determining inertia parameters
DE102015211387A1 (en) * 2015-06-19 2016-12-22 Robert Bosch Gmbh Three-axis spin sensor
JP6146592B2 (en) * 2015-10-27 2017-06-14 セイコーエプソン株式会社 Physical quantity sensor, electronic equipment
ITUA20161498A1 (en) * 2016-03-09 2017-09-09 St Microelectronics Srl MICROMECHANICAL DETECTION STRUCTURE OF A MEMS SENSOR DEVICE, IN PARTICULAR OF A MEMS GYRO, WITH IMPROVED DRIVE CHARACTERISTICS
US20180031602A1 (en) * 2016-07-27 2018-02-01 Lumedyne Technologies Incorporated Converting rotational motion to linear motion
US10234477B2 (en) 2016-07-27 2019-03-19 Google Llc Composite vibratory in-plane accelerometer
US10697994B2 (en) 2017-02-22 2020-06-30 Semiconductor Components Industries, Llc Accelerometer techniques to compensate package stress
DE102018211755A1 (en) * 2018-07-13 2020-01-16 Infineon Technologies Ag AMPLITUDE DETECTION, AMPLITUDE CONTROL AND DIRECTION DETECTION OF A VIBRATION OF A VIBRATION BODY
US11099207B2 (en) * 2018-10-25 2021-08-24 Analog Devices, Inc. Low-noise multi-axis accelerometers and related methods
EP3671116B1 (en) * 2018-12-19 2021-11-17 Murata Manufacturing Co., Ltd. Synchronized multi-axis gyroscope
EP3671118B1 (en) 2018-12-19 2021-08-25 Murata Manufacturing Co., Ltd. Vibration-robust multiaxis gyroscope
WO2020145203A1 (en) * 2019-01-08 2020-07-16 Panasonic Intellectual Property Management Co., Ltd. Sensing device
JP6897806B2 (en) * 2019-02-15 2021-07-07 株式会社村田製作所 Balanced multi-axis gyroscope
EP3696503B1 (en) * 2019-02-15 2022-10-26 Murata Manufacturing Co., Ltd. Vibration-robust multiaxis gyroscope
CN109900262B (en) * 2019-04-08 2021-08-10 瑞声科技(新加坡)有限公司 Gyroscope
US11891297B2 (en) * 2019-07-05 2024-02-06 Aac Acoustic Technologies (Shenzhen) Co., Ltd. Motion control structure and actuator
JP7188311B2 (en) * 2019-07-31 2022-12-13 セイコーエプソン株式会社 Gyro sensors, electronic devices, and mobile objects
US11609091B2 (en) * 2020-11-16 2023-03-21 Knowles Electronics, Llc Microelectromechanical systems device including a proof mass and movable plate
CN113091722A (en) * 2021-04-02 2021-07-09 瑞声开泰科技(武汉)有限公司 Three-axis micromechanical gyroscope and angular velocity measuring method
CN116147600A (en) * 2021-10-27 2023-05-23 苏州明皜传感科技股份有限公司 Micro electromechanical multi-axis angular velocity sensor
CN114459660A (en) * 2021-12-14 2022-05-10 北京无线电计量测试研究所 Decoupling space six-dimensional force measuring device
CN114459453A (en) * 2021-12-24 2022-05-10 瑞声开泰科技(武汉)有限公司 Micromechanical gyroscope and electronic product
CN114353776A (en) * 2021-12-31 2022-04-15 瑞声开泰科技(武汉)有限公司 MEMS gyroscope based on rotation mode

Citations (73)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4159125A (en) 1977-11-04 1979-06-26 General Motors Corporation Uncoupled strut suspension system
US5447068A (en) 1994-03-31 1995-09-05 Ford Motor Company Digital capacitive accelerometer
US5728936A (en) 1995-08-16 1998-03-17 Robert Bosch Gmbh Rotary speed sensor
DE19641284C1 (en) 1996-10-07 1998-05-20 Inst Mikro Und Informationstec Rotation rate sensor with decoupled orthogonal primary and secondary vibrations
US5889207A (en) 1996-05-03 1999-03-30 Robert Bosch Gmbh Micromechanical rate of rotation sensor having ring with drive element and detection element
US5895850A (en) 1994-04-23 1999-04-20 Robert Bosch Gmbh Micromechanical resonator of a vibration gyrometer
EP0971208A2 (en) 1998-07-10 2000-01-12 Murata Manufacturing Co., Ltd. Angular velocity sensor
US6062082A (en) 1995-06-30 2000-05-16 Robert Bosch Gmbh Micromechanical acceleration or coriolis rotation-rate sensor
WO2000029855A1 (en) 1998-10-14 2000-05-25 Irvine Sensors Corporation Multi-element micro-gyro
US6189381B1 (en) * 1999-04-26 2001-02-20 Sitek, Inc. Angular rate sensor made from a structural wafer of single crystal silicon
US6230563B1 (en) 1998-06-09 2001-05-15 Integrated Micro Instruments, Inc. Dual-mass vibratory rate gyroscope with suppressed translational acceleration response and quadrature-error correction capability
US6244111B1 (en) 1998-10-30 2001-06-12 Robert Bosch Gmbh Micromechanical gradient sensor
US6250157B1 (en) * 1998-06-22 2001-06-26 Aisin Seiki Kabushiki Kaisha Angular rate sensor
US6250156B1 (en) 1996-05-31 2001-06-26 The Regents Of The University Of California Dual-mass micromachined vibratory rate gyroscope
US6308567B1 (en) 1998-12-10 2001-10-30 Denso Corporation Angular velocity sensor
US6374672B1 (en) 2000-07-28 2002-04-23 Litton Systems, Inc. Silicon gyro with integrated driving and sensing structures
EP1253399A1 (en) 2001-04-27 2002-10-30 STMicroelectronics S.r.l. Integrated gyroscope of semiconductor material
US20020189351A1 (en) 2001-06-14 2002-12-19 Reeds John W. Angular rate sensor having a sense element constrained to motion about a single axis and flexibly attached to a rotary drive mass
US6508124B1 (en) 1999-09-10 2003-01-21 Stmicroelectronics S.R.L. Microelectromechanical structure insensitive to mechanical stresses
US6513380B2 (en) 2001-06-19 2003-02-04 Microsensors, Inc. MEMS sensor with single central anchor and motion-limiting connection geometry
US6520017B1 (en) 1999-08-12 2003-02-18 Robert Bosch Gmbh Micromechanical spin angular acceleration sensor
US6535800B2 (en) 2001-05-29 2003-03-18 Delphi Technologies, Inc. Vehicle rollover sensing using angular rate sensors
US6626039B1 (en) 1999-09-17 2003-09-30 Millisensor Systems And Actuators, Inc. Electrically decoupled silicon gyroscope
EP1365211A1 (en) 2002-05-21 2003-11-26 STMicroelectronics S.r.l. Integrated gyroscope of semiconductor material with at least one sensitive axis in the sensor plane
US20040035204A1 (en) * 2001-04-27 2004-02-26 Stmicroelectronics S.R.L. Integrated gyroscope of semiconductor material with at least one sensitive axis in the sensor plane
US6715352B2 (en) 2001-06-26 2004-04-06 Microsensors, Inc. Method of designing a flexure system for tuning the modal response of a decoupled micromachined gyroscope and a gyroscoped designed according to the method
US6722197B2 (en) 2001-06-19 2004-04-20 Honeywell International Inc. Coupled micromachined structure
US6752017B2 (en) 2001-02-21 2004-06-22 Robert Bosch Gmbh Rotation speed sensor
US6837107B2 (en) 2003-04-28 2005-01-04 Analog Devices, Inc. Micro-machined multi-sensor providing 1-axis of acceleration sensing and 2-axes of angular rate sensing
US6848304B2 (en) 2003-04-28 2005-02-01 Analog Devices, Inc. Six degree-of-freedom micro-machined multi-sensor
US6894576B2 (en) 1999-11-02 2005-05-17 Eta Sa Fabriques D'ebauches Temperature compensation mechanism for a micromechanical ring resonator
US6918298B2 (en) 2002-12-24 2005-07-19 Samsung Electro-Mechanics Co., Ltd. Horizontal and tuning fork vibratory microgyroscope
JP2005241500A (en) 2004-02-27 2005-09-08 Mitsubishi Electric Corp Angular velocity sensor
US6952965B2 (en) * 2002-12-24 2005-10-11 Samsung Electronics Co., Ltd. Vertical MEMS gyroscope by horizontal driving
DE102004017480A1 (en) 2004-04-08 2005-10-27 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Rotary rotation rate sensor with mechanically decoupled vibration modes
EP1617178A1 (en) 2004-07-12 2006-01-18 STMicroelectronics S.r.l. Micro-electro-mechanical structure having electrically insulated regions and manufacturing process thereof
EP1619471A1 (en) 2004-07-19 2006-01-25 Samsung Electronics Co., Ltd. MEMS gyroscope having coupling springs
EP1624286A1 (en) 2004-08-03 2006-02-08 STMicroelectronics S.r.l. Micro-electro-mechanical sensor with force feedback loop
WO2006043890A1 (en) 2004-10-20 2006-04-27 Imego Ab Sensor device
US20060112764A1 (en) 2004-12-01 2006-06-01 Denso Corporation Angular velocity detector having inertial mass oscillating in rotational direction
CN1813194A (en) 2003-04-28 2006-08-02 模拟器件公司 Micro-machined multi-sensor providing 1-axis of acceleration sensing and 2-axes of angular rate sensing
US7100446B1 (en) 2004-07-20 2006-09-05 The Regents Of The University Of California Distributed-mass micromachined gyroscopes operated with drive-mode bandwidth enhancement
US7155976B2 (en) 2005-01-05 2007-01-02 Industrial Technology Research Institute Rotation sensing apparatus and method for manufacturing the same
US20070062282A1 (en) 2005-09-07 2007-03-22 Hitachi, Ltd. Combined sensor and its fabrication method
US7240552B2 (en) 2005-06-06 2007-07-10 Bei Technologies, Inc. Torsional rate sensor with momentum balance and mode decoupling
WO2007086849A1 (en) 2006-01-25 2007-08-02 The Regents Of The University Of California Robust six degree-of-freedom micromachined gyroscope with anti-phase drive scheme and method of operation of the same
US7258012B2 (en) 2003-02-24 2007-08-21 University Of Florida Research Foundation, Inc. Integrated monolithic tri-axial micromachined accelerometer
EP1832841A1 (en) 2006-03-10 2007-09-12 STMicroelectronics S.r.l. Microelectromechanical integrated sensor structure with rotary driving motion
US7284429B2 (en) 2003-09-09 2007-10-23 Bernard Chaumet Micromachined double tuning-fork gyrometer with detection in the plane of the machined wafer
DE102007012163A1 (en) 2006-03-10 2007-10-25 Continental Teves Ag & Co. Ohg Rotational speed sensor e.g. micro-electro mechanical system, for use in e.g. electronic stability program control system, has torsion spring permitting torsion deflections of seismic masses, and base units coupled by coupling bar
WO2007145113A1 (en) 2006-06-16 2007-12-21 Sony Corporation Inertial sensor
US7322242B2 (en) 2004-08-13 2008-01-29 Stmicroelectronics S.R.L. Micro-electromechanical structure with improved insensitivity to thermomechanical stresses induced by the package
US7347094B2 (en) 2004-04-14 2008-03-25 Analog Devices, Inc. Coupling apparatus for inertial sensors
DE102006046772A1 (en) 2006-09-29 2008-04-03 Siemens Ag Rotating rate measuring arrangement, has capacitive units formed by fixed electrodes and by other electrodes that are connected with fixed connection, where exciting voltages are supplied to fixed electrodes of capacitive units
US7398683B2 (en) 2003-02-11 2008-07-15 Vti Technologies Oy Capacitive acceleration sensor
EP1962054A1 (en) 2007-02-13 2008-08-27 STMicroelectronics S.r.l. Microelectomechanical gyroscope with open loop reading device and control method of a microelectromechanical gyroscope
US20080276706A1 (en) 2004-09-27 2008-11-13 Conti Temic Microelectronic Gmbh Rotation Speed Sensor
US7454246B2 (en) 2005-09-08 2008-11-18 Massachusetts Eye & Ear Infirmary Sensor signal alignment
US7461552B2 (en) 2006-10-23 2008-12-09 Custom Sensors & Technologies, Inc. Dual axis rate sensor
US20090064780A1 (en) 2007-09-11 2009-03-12 Stmicroelectronics S.R.L. Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
WO2009033915A1 (en) 2007-09-10 2009-03-19 Continental Teves Ag & Co. Ohg Micromechanical rate-of-rotation sensor
US7513155B2 (en) 2005-12-05 2009-04-07 Hitachi, Ltd. Inertial sensor
WO2009087858A1 (en) 2008-01-07 2009-07-16 Murata Manufacturing Co., Ltd. Angular velocity sensor
US7677099B2 (en) * 2007-11-05 2010-03-16 Invensense Inc. Integrated microelectromechanical systems (MEMS) vibrating mass Z-axis rate sensor
US20100126272A1 (en) * 2008-11-26 2010-05-27 Stmicroelectronics S.R.L. Uniaxial or biaxial microelectromechanical gyroscope with improved sensitivity to angular velocity detection
US20100126269A1 (en) * 2008-11-26 2010-05-27 Stmicroelectronics S.R.L. Microelectromechanical gyroscope with rotary driving motion and improved electrical properties
US20100154541A1 (en) * 2008-12-23 2010-06-24 Stmicroelectronics S.R.L. Microelectromechanical gyroscope with enhanced rejection of acceleration noises
US20100199764A1 (en) 2007-07-31 2010-08-12 Sensordynamics Ag Micromechanical rate-of-rotation sensor
US7797998B2 (en) 2003-08-13 2010-09-21 Sercel Accelerometer with reduced extraneous vibrations owing to improved electrode shape
US20100281977A1 (en) * 2009-05-11 2010-11-11 Stmicroelectronics S.R.I. Microelectromechanical structure with enhanced rejection of acceleration noise
US7907177B2 (en) 2006-11-16 2011-03-15 Eastman Kodak Company Method for eliminating error in camera having angular velocity detection system
US20120060604A1 (en) 2007-11-15 2012-03-15 Reinhard Neul Yaw-rate sensor
US8342023B2 (en) 2007-06-29 2013-01-01 Northrop Grumman Litef Gmbh Coriolis gyro

Patent Citations (92)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4159125A (en) 1977-11-04 1979-06-26 General Motors Corporation Uncoupled strut suspension system
US5447068A (en) 1994-03-31 1995-09-05 Ford Motor Company Digital capacitive accelerometer
US5895850A (en) 1994-04-23 1999-04-20 Robert Bosch Gmbh Micromechanical resonator of a vibration gyrometer
US6062082A (en) 1995-06-30 2000-05-16 Robert Bosch Gmbh Micromechanical acceleration or coriolis rotation-rate sensor
US5728936A (en) 1995-08-16 1998-03-17 Robert Bosch Gmbh Rotary speed sensor
US5889207A (en) 1996-05-03 1999-03-30 Robert Bosch Gmbh Micromechanical rate of rotation sensor having ring with drive element and detection element
US6250156B1 (en) 1996-05-31 2001-06-26 The Regents Of The University Of California Dual-mass micromachined vibratory rate gyroscope
DE19641284C1 (en) 1996-10-07 1998-05-20 Inst Mikro Und Informationstec Rotation rate sensor with decoupled orthogonal primary and secondary vibrations
US6349597B1 (en) 1996-10-07 2002-02-26 Hahn-Schickard-Gesellschaft Fur Angewandte Forschung E.V. Rotation rate sensor with uncoupled mutually perpendicular primary and secondary oscillations
US6230563B1 (en) 1998-06-09 2001-05-15 Integrated Micro Instruments, Inc. Dual-mass vibratory rate gyroscope with suppressed translational acceleration response and quadrature-error correction capability
US6250157B1 (en) * 1998-06-22 2001-06-26 Aisin Seiki Kabushiki Kaisha Angular rate sensor
EP0971208A2 (en) 1998-07-10 2000-01-12 Murata Manufacturing Co., Ltd. Angular velocity sensor
WO2000029855A1 (en) 1998-10-14 2000-05-25 Irvine Sensors Corporation Multi-element micro-gyro
US6244111B1 (en) 1998-10-30 2001-06-12 Robert Bosch Gmbh Micromechanical gradient sensor
US6308567B1 (en) 1998-12-10 2001-10-30 Denso Corporation Angular velocity sensor
US6189381B1 (en) * 1999-04-26 2001-02-20 Sitek, Inc. Angular rate sensor made from a structural wafer of single crystal silicon
US6520017B1 (en) 1999-08-12 2003-02-18 Robert Bosch Gmbh Micromechanical spin angular acceleration sensor
US6508124B1 (en) 1999-09-10 2003-01-21 Stmicroelectronics S.R.L. Microelectromechanical structure insensitive to mechanical stresses
US6626039B1 (en) 1999-09-17 2003-09-30 Millisensor Systems And Actuators, Inc. Electrically decoupled silicon gyroscope
US6894576B2 (en) 1999-11-02 2005-05-17 Eta Sa Fabriques D'ebauches Temperature compensation mechanism for a micromechanical ring resonator
US6374672B1 (en) 2000-07-28 2002-04-23 Litton Systems, Inc. Silicon gyro with integrated driving and sensing structures
US6752017B2 (en) 2001-02-21 2004-06-22 Robert Bosch Gmbh Rotation speed sensor
US20040035204A1 (en) * 2001-04-27 2004-02-26 Stmicroelectronics S.R.L. Integrated gyroscope of semiconductor material with at least one sensitive axis in the sensor plane
US20020189354A1 (en) * 2001-04-27 2002-12-19 Stmicroelectronics S.R.I. Integrated gyroscope of semiconductor material
EP1253399A1 (en) 2001-04-27 2002-10-30 STMicroelectronics S.r.l. Integrated gyroscope of semiconductor material
US6928872B2 (en) 2001-04-27 2005-08-16 Stmicroelectronics S.R.L. Integrated gyroscope of semiconductor material with at least one sensitive axis in the sensor plane
US6766689B2 (en) 2001-04-27 2004-07-27 Stmicroelectronics S.R.L. Integrated gyroscope of semiconductor material
US6535800B2 (en) 2001-05-29 2003-03-18 Delphi Technologies, Inc. Vehicle rollover sensing using angular rate sensors
WO2002103364A2 (en) 2001-06-14 2002-12-27 Microsensors, Inc. Angular rate sensor having a sense element constrained to motion about a single axis and flexibly attached to a rotary drive mass
US20020189351A1 (en) 2001-06-14 2002-12-19 Reeds John W. Angular rate sensor having a sense element constrained to motion about a single axis and flexibly attached to a rotary drive mass
US6722197B2 (en) 2001-06-19 2004-04-20 Honeywell International Inc. Coupled micromachined structure
US6513380B2 (en) 2001-06-19 2003-02-04 Microsensors, Inc. MEMS sensor with single central anchor and motion-limiting connection geometry
US6715352B2 (en) 2001-06-26 2004-04-06 Microsensors, Inc. Method of designing a flexure system for tuning the modal response of a decoupled micromachined gyroscope and a gyroscoped designed according to the method
EP1365211A1 (en) 2002-05-21 2003-11-26 STMicroelectronics S.r.l. Integrated gyroscope of semiconductor material with at least one sensitive axis in the sensor plane
US6918298B2 (en) 2002-12-24 2005-07-19 Samsung Electro-Mechanics Co., Ltd. Horizontal and tuning fork vibratory microgyroscope
US6952965B2 (en) * 2002-12-24 2005-10-11 Samsung Electronics Co., Ltd. Vertical MEMS gyroscope by horizontal driving
US7398683B2 (en) 2003-02-11 2008-07-15 Vti Technologies Oy Capacitive acceleration sensor
US7258012B2 (en) 2003-02-24 2007-08-21 University Of Florida Research Foundation, Inc. Integrated monolithic tri-axial micromachined accelerometer
US6848304B2 (en) 2003-04-28 2005-02-01 Analog Devices, Inc. Six degree-of-freedom micro-machined multi-sensor
CN1813194A (en) 2003-04-28 2006-08-02 模拟器件公司 Micro-machined multi-sensor providing 1-axis of acceleration sensing and 2-axes of angular rate sensing
US6837107B2 (en) 2003-04-28 2005-01-04 Analog Devices, Inc. Micro-machined multi-sensor providing 1-axis of acceleration sensing and 2-axes of angular rate sensing
US7797998B2 (en) 2003-08-13 2010-09-21 Sercel Accelerometer with reduced extraneous vibrations owing to improved electrode shape
US7284429B2 (en) 2003-09-09 2007-10-23 Bernard Chaumet Micromachined double tuning-fork gyrometer with detection in the plane of the machined wafer
JP2005241500A (en) 2004-02-27 2005-09-08 Mitsubishi Electric Corp Angular velocity sensor
DE102004017480A1 (en) 2004-04-08 2005-10-27 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Rotary rotation rate sensor with mechanically decoupled vibration modes
US7520169B2 (en) 2004-04-08 2009-04-21 Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V. Angular rate sensor featuring mechanically decoupled oscillation modes
US7347094B2 (en) 2004-04-14 2008-03-25 Analog Devices, Inc. Coupling apparatus for inertial sensors
EP1617178A1 (en) 2004-07-12 2006-01-18 STMicroelectronics S.r.l. Micro-electro-mechanical structure having electrically insulated regions and manufacturing process thereof
US7437933B2 (en) 2004-07-12 2008-10-21 Stmicroelectronics S.R.L. Micro-electro-mechanical structure having electrically insulated regions and manufacturing process thereof
EP1619471A1 (en) 2004-07-19 2006-01-25 Samsung Electronics Co., Ltd. MEMS gyroscope having coupling springs
US7100446B1 (en) 2004-07-20 2006-09-05 The Regents Of The University Of California Distributed-mass micromachined gyroscopes operated with drive-mode bandwidth enhancement
EP1624286A1 (en) 2004-08-03 2006-02-08 STMicroelectronics S.r.l. Micro-electro-mechanical sensor with force feedback loop
US7481111B2 (en) 2004-08-03 2009-01-27 Stmicroelectronics S.R.L. Micro-electro-mechanical sensor with force feedback loop
US7322242B2 (en) 2004-08-13 2008-01-29 Stmicroelectronics S.R.L. Micro-electromechanical structure with improved insensitivity to thermomechanical stresses induced by the package
US20080276706A1 (en) 2004-09-27 2008-11-13 Conti Temic Microelectronic Gmbh Rotation Speed Sensor
WO2006043890A1 (en) 2004-10-20 2006-04-27 Imego Ab Sensor device
US20060112764A1 (en) 2004-12-01 2006-06-01 Denso Corporation Angular velocity detector having inertial mass oscillating in rotational direction
US7155976B2 (en) 2005-01-05 2007-01-02 Industrial Technology Research Institute Rotation sensing apparatus and method for manufacturing the same
US7240552B2 (en) 2005-06-06 2007-07-10 Bei Technologies, Inc. Torsional rate sensor with momentum balance and mode decoupling
US20070062282A1 (en) 2005-09-07 2007-03-22 Hitachi, Ltd. Combined sensor and its fabrication method
US7454246B2 (en) 2005-09-08 2008-11-18 Massachusetts Eye & Ear Infirmary Sensor signal alignment
US7513155B2 (en) 2005-12-05 2009-04-07 Hitachi, Ltd. Inertial sensor
WO2007086849A1 (en) 2006-01-25 2007-08-02 The Regents Of The University Of California Robust six degree-of-freedom micromachined gyroscope with anti-phase drive scheme and method of operation of the same
US7694563B2 (en) * 2006-03-10 2010-04-13 Stmicroelectronics S.R.L. Microelectromechanical integrated sensor structure with rotary driving motion
US8261614B2 (en) 2006-03-10 2012-09-11 Continental Teves Ag & Co. Ohg Rotational speed sensor having a coupling bar
DE102007012163A1 (en) 2006-03-10 2007-10-25 Continental Teves Ag & Co. Ohg Rotational speed sensor e.g. micro-electro mechanical system, for use in e.g. electronic stability program control system, has torsion spring permitting torsion deflections of seismic masses, and base units coupled by coupling bar
US20070214883A1 (en) 2006-03-10 2007-09-20 Stmicroelectronics S.R.L. Microelectromechanical integrated sensor structure with rotary driving motion
EP1832841A1 (en) 2006-03-10 2007-09-12 STMicroelectronics S.r.l. Microelectromechanical integrated sensor structure with rotary driving motion
WO2007145113A1 (en) 2006-06-16 2007-12-21 Sony Corporation Inertial sensor
US8096181B2 (en) 2006-06-16 2012-01-17 Sony Corporation Inertial sensor
DE102006046772A1 (en) 2006-09-29 2008-04-03 Siemens Ag Rotating rate measuring arrangement, has capacitive units formed by fixed electrodes and by other electrodes that are connected with fixed connection, where exciting voltages are supplied to fixed electrodes of capacitive units
US7461552B2 (en) 2006-10-23 2008-12-09 Custom Sensors & Technologies, Inc. Dual axis rate sensor
US7907177B2 (en) 2006-11-16 2011-03-15 Eastman Kodak Company Method for eliminating error in camera having angular velocity detection system
EP1962054A1 (en) 2007-02-13 2008-08-27 STMicroelectronics S.r.l. Microelectomechanical gyroscope with open loop reading device and control method of a microelectromechanical gyroscope
US8037756B2 (en) 2007-02-13 2011-10-18 Stmicroelectronics S.R.L. Microelectromechanical gyroscope with open loop reading device and control method
US8342023B2 (en) 2007-06-29 2013-01-01 Northrop Grumman Litef Gmbh Coriolis gyro
US20100199764A1 (en) 2007-07-31 2010-08-12 Sensordynamics Ag Micromechanical rate-of-rotation sensor
US8353212B2 (en) 2007-07-31 2013-01-15 Maxim Integrated Products Gmbh Micromechanical rate-of-rotation sensor
WO2009033915A1 (en) 2007-09-10 2009-03-19 Continental Teves Ag & Co. Ohg Micromechanical rate-of-rotation sensor
US8549919B2 (en) 2007-09-10 2013-10-08 Continental Teves Ag & Co. Ohg Micromechanical rotation rate sensor with a coupling bar and suspension spring elements for quadrature suppression
US20090100930A1 (en) * 2007-09-11 2009-04-23 Stmicroelectronics S.R.L. High sensitivity microelectromechanical sensor with rotary driving motion
US20090064780A1 (en) 2007-09-11 2009-03-12 Stmicroelectronics S.R.L. Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
US8042394B2 (en) 2007-09-11 2011-10-25 Stmicroelectronics S.R.L. High sensitivity microelectromechanical sensor with rotary driving motion
US8042396B2 (en) 2007-09-11 2011-10-25 Stmicroelectronics S.R.L. Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
US7677099B2 (en) * 2007-11-05 2010-03-16 Invensense Inc. Integrated microelectromechanical systems (MEMS) vibrating mass Z-axis rate sensor
US20120060604A1 (en) 2007-11-15 2012-03-15 Reinhard Neul Yaw-rate sensor
US8272267B2 (en) 2008-01-07 2012-09-25 Murata Manufacturing Co., Ltd. Angular velocity sensor
WO2009087858A1 (en) 2008-01-07 2009-07-16 Murata Manufacturing Co., Ltd. Angular velocity sensor
US20100126269A1 (en) * 2008-11-26 2010-05-27 Stmicroelectronics S.R.L. Microelectromechanical gyroscope with rotary driving motion and improved electrical properties
US20100126272A1 (en) * 2008-11-26 2010-05-27 Stmicroelectronics S.R.L. Uniaxial or biaxial microelectromechanical gyroscope with improved sensitivity to angular velocity detection
US20100154541A1 (en) * 2008-12-23 2010-06-24 Stmicroelectronics S.R.L. Microelectromechanical gyroscope with enhanced rejection of acceleration noises
US20100281977A1 (en) * 2009-05-11 2010-11-11 Stmicroelectronics S.R.I. Microelectromechanical structure with enhanced rejection of acceleration noise

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
Durante et al., "Microelectromechanical Integrated Sensor Stucture With Rotary Driving Motion," Office Action mailed Apr. 24, 2009, in U.S. Appl. No. 11/684,243, filed Mar. 9, 2007, 10 pages.
Ing. Luca Coronato, "Re: Reissue U.S. Appl. No. 14/062,671: Microelectromechanical Sensor With Improved Mechanical Decoupling of Sensing and Driving Modes," Refusal Letter, dated Mar. 31, 2015, and received on Apr. 2, 2015, 3 pages.
Schofield et al., "Multi-Degree of Freedom Tuning Fork Gyroscope Demonstrating Shock Rejection," IEEE Sensors 2007 Conference, Atlanta, Georgia, Oct. 28-31, 2007, pp. 120-123.
US Office Action mailed Apr. 24, 2009, in U.S. Appl. No. 11/684,243, filed Mar. 9, 2007.

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150168437A1 (en) * 2012-05-29 2015-06-18 Denso Corporation Physical quantity sensor
US9476897B2 (en) * 2012-05-29 2016-10-25 Denso Corporation Physical quantity sensor
US20170285061A1 (en) * 2016-03-31 2017-10-05 Stmicroelectronics S.R.L. Accelerometric sensor in mems technology having high accuracy and low sensitivity to temperature and ageing
US10591505B2 (en) * 2016-03-31 2020-03-17 Stmicroelectronics S.R.L. Accelerometric sensor in MEMS technology having high accuracy and low sensitivity to temperature and ageing
US11408904B2 (en) 2016-03-31 2022-08-09 Stmicroelectronics S.R.L. Accelerometric sensor in mems technology having high accuracy and low sensitivity to temperature and ageing
US12050102B2 (en) 2019-09-30 2024-07-30 Stmicroelectronics S.R.L. Waterproof MEMS button device, input device comprising the MEMS button device and electronic apparatus

Also Published As

Publication number Publication date
US20090100930A1 (en) 2009-04-23
USRE45792E1 (en) 2015-11-03
US20090064780A1 (en) 2009-03-12
US8042396B2 (en) 2011-10-25
US8042394B2 (en) 2011-10-25

Similar Documents

Publication Publication Date Title
USRE45855E1 (en) Microelectromechanical sensor with improved mechanical decoupling of sensing and driving modes
EP2192382B1 (en) Microelectromechanical gyroscope with rotary driving motion and improved electrical properties
US11815354B2 (en) Drive and sense balanced, semi-coupled 3-axis gyroscope
EP2192383B1 (en) Uniaxial or biaxial microelectromechanical gyroscope with improved sensitivity to angular velocity detection
US11841228B2 (en) Drive and sense balanced, fully-coupled 3-axis gyroscope
US7694563B2 (en) Microelectromechanical integrated sensor structure with rotary driving motion
KR101105059B1 (en) Method of making an x-y axis dual-mass tuning fork gyroscope with vertically integrated electronics and wafer-scale hermetic packaging
KR101700124B1 (en) Micromachined inertial sensor devices
US11015933B2 (en) Micromechanical detection structure for a MEMS sensor device, in particular a MEMS gyroscope, with improved driving features
US9315376B2 (en) Planar structure for a triaxial gyrometer
US20230314469A1 (en) Mems tri-axial accelerometer with one or more decoupling elements

Legal Events

Date Code Title Description
MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 8

FEPP Fee payment procedure

Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

LAPS Lapse for failure to pay maintenance fees

Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY