Stmicroelectronics S.r.l.

Luca Giuseppe Falorni

Carlo Valzasina

Luca Guerinoni

Gabriele Gattere

Alessandro Tocchio

Matteo Fabio Brunetto

Daniele Prati

Claudia Comi

Valentina Zega

Patrick Fedeli

Roberto Carminati

Massimo Greppi

Paolo Aranzulla

Fabiano Frigoli

Giuseppe Ballotta

Giacomo Langfelder

Francesco Braghin

Ferruccio Resta

Damiano Milani

Leonardo Gaffuri Pagani

Paola Carulli

Mohammad Izadi

A microelectromechanical gyroscope is provided with a detection structure having: a substrate with a top surface parallel to a horizontal plane (xy); a mobile mass, suspended above the substrate to perform, as a function of a first angular velocity (Ω) around a first axis (x) of the horizontal plane (xy), at least a first detection movement of rotation around a second axis (y) of the horizontal plane; and a first and a second stator elements integral with the substrate and arranged underneath the mobile mass to define a capacitive coupling, a capacitance value thereof is indicative of the first angular velocity (Ω). The detection structure has a single mechanical anchorage structure for anchoring both the mobile mass and the stator elements to the substrate, arranged internally with respect to the mobile mass, which is coupled to this single mechanical anchorage structure by coupling elastic elements yielding to torsion around the second axis; the stator elements are integrally coupled to the single mechanical anchorage structure in an arrangement suspended above the top surface of the substrate.

Microelectromechanical gyroscope with out-of-plane detection movement

A microelectromechanical device includes a substrate, a first structural layer, and a second structural layer of semiconductor material. A sensing mass extends in the first structural layer and is coupled to the substrate by first elastic connections to enable oscillation of the sensing mass in a sensing direction perpendicular to the substrate by a maximum amount relative to a resting position of the sensing mass. An out-of-plane stopper structure includes an anchorage fixed to the substrate and a mechanical end-of-travel structure, which extends in the second structural layer, faces the sensing mass, and is separated therefrom by a gap having a width smaller than the maximum displacement distance of the sensing mass. The mechanical end-of-travel structure is coupled to the anchorage by second elastic connections that enable movement of the mechanical end-of-travel structure in the sensing direction in response to an impact of the sensing mass.

Microelectromechanical device with out-of-plane stopper structure

A microelectromechanical gyroscope includes: the support structure; a sensing mass, coupled to the support structure with degrees of freedom along a driving direction and a sensing direction perpendicular to each other; and a calibration structure facing the sensing mass and separated from the sensing mass by a gap having an average width, the calibration structure being movable with respect to the sensing mass so that displacements of the calibration structure cause variations in the average width of the gap. A calibration actuator controls a relative position of the calibration structure with respect to the sensing mass and the average width of the gap.

Microelectromechanical gyroscope and method for compensating an output thermal drift in a microelectromechanical gyroscope

A frequency modulation MEMS triaxial gyroscope, having two mobile masses; a first and a second driving body coupled to the mobile masses through elastic elements rigid in a first direction and compliant in a second direction transverse to the first direction; and a third and a fourth driving body coupled to the mobile masses through elastic elements rigid in the second direction and compliant in the first direction. A first and a second driving element are coupled to the first and second driving bodies for causing the mobile masses to translate in the first direction in phase opposition. A third and a fourth driving element are coupled to the third and fourth driving bodies for causing the mobile masses to translate in the second direction and in phase opposition. An out-of-plane driving element is coupled to the first and second mobile masses for causing a translation in a third direction, in phase opposition. Movement-sensing electrodes generate frequency signals as a function of external angular velocities.

Frequency modulation MEMS triaxial gyroscope

The MEMS gyroscope is formed by a substrate, a first mass and a second mass, wherein the first and the second masses are suspended over the substrate and extend, at rest, in a plane of extension defining a first direction and a second direction transverse to the first direction. The MEMS gyroscope further has a drive structure coupled to the first mass and configured, in use, to cause a movement of the first mass in the first direction, and an elastic coupling structure, which extends between the first mass and the second mass and is configured to couple the movement of the first mass in the first direction with a movement of the second mass in the second direction. The elastic coupling structure has a first portion having a first stiffness and a second portion having a second stiffness greater than the first stiffness.

MEMS gyroscope having an improved rejection of the quadrature error

In an embodiment a circuit includes an inertial measurement unit configured to be oscillated via a driving signal provided by driving circuitry, a lock-in amplifier configured to receive a sensing signal from the inertial measurement unit and a reference demodulation signal which is a function of the driving signal and provide an inertial measurement signal based on the sensing signal, wherein the reference demodulation signal is affected by a variable phase error, phase meter circuitry configured to receive the driving signal and the sensing signal and provide, as a function of a phase difference between the driving signal and the sensing signal, a phase correction signal for the reference demodulation signal and a correction node configured to apply the phase correction signal to the reference demodulation signal so that, in response to the phase correction signal being applied to the reference demodulation signal, the phase error is maintained in a vicinity of a reference value.

Inertial measurement circuit, corresponding device and method

The MEMS gyroscope has a mobile mass carried by a supporting structure to move in a driving direction and in a first sensing direction, perpendicular to each other. A driving structure governs movement of the mobile mass in the driving direction at a driving frequency. A movement sensing structure is coupled to the mobile mass and detects the movement of the mobile mass in the sensing direction. A quadrature-injection structure is coupled to the mobile mass and causes a first and a second movement of the mobile mass in the sensing direction in a first calibration half-period and, respectively, a second calibration half-period. The movement-sensing structure supplies a sensing signal having an amplitude switching between a first and a second value that depend upon the movement of the mobile mass as a result of an external angular velocity and of the first and second quadrature movements. The first and second values of the sensing signal are subtracted from each other and compared with a stored difference value to supply information of variation of the scale factor.

MEMS gyroscope with calibration of the scale factor in real time and calibration method thereof

A multi-axis MEMS gyroscope includes a micromechanical detection structure having a substrate, a driving-mass arrangement, a driven-mass arrangement with a central window, and a sensing-mass arrangement which undergoes sensing movements in the presence of angular velocities about a first horizontal axis and a second horizontal axis. A sensing-electrode arrangement is fixed with respect to the substrate and is set underneath the sensing-mass arrangement. An anchorage assembly is set within the central window for constraining the driven-mass arrangement to the substrate at anchorage elements. The anchorage assembly includes a rigid structure suspended above the substrate that is elastically coupled to the driven mass by elastic connection elements at a central portion, and is coupled to the anchorage elements by elastic decoupling elements at end portions thereof.

Micromechanical detection structure of a MEMS multi-axis gyroscope, with reduced drifts of corresponding electrical parameters

A microelectromechanical gyroscope includes: a substrate; a stator sensing structure fixed to the substrate; a first mass elastically constrained to the substrate and movable with respect to the substrate in a first direction; a second mass elastically constrained to the first mass and movable with respect to the first mass in a second direction; and a third mass elastically constrained to the second mass and to the substrate and capacitively coupled to the stator sensing structure, the third mass being movable with respect to the substrate in the second direction and with respect to the second mass in the first direction.

Microelectromechanical gyroscope for sensing angular rate and method of sensing angular rate

A micromechanical detection structure includes a substrate of semiconductor material and a driving-mass arrangement is coupled to a set of driving electrodes and driven in a driving movement following upon biasing of the set of driving electrodes. A first anchorage unit is coupled to the driving-mass arrangement for elastically coupling the driving-mass arrangement to the substrate at first anchorages. A driven-mass arrangement is elastically coupled to the driving-mass arrangement by a coupling unit and designed to be driven by the driving movement. A second anchorage unit is coupled to the driven-mass arrangement for elastically coupling the driven-mass arrangement to the substrate at second anchorages. Following upon the driving movement, the resultant of the forces and of the torques exerted on the substrate at the first and second anchorages is substantially zero.

Micromechanical detection structure for a MEMS sensor device, in particular a MEMS gyroscope, with improved driving features

A MEMS gyroscope is equipped with: at least a first mobile mass suspended from the top of a substrate by means of elastic suspension elements coupled to anchor points rigidly fixed to the substrate, in such a manner as to be actuated in an actuating movement along a first axis of a horizontal plane and to carry out a measurement movement along a vertical axis, transverse to the horizontal plane, in response to a first angular velocity acting about a second axis of the horizontal plane, transverse to the first axis. The elastic suspension elements are configured in such a manner as to internally compensate unwanted displacements out of the horizontal plane along the vertical axis originating from the actuating movement, such that the mobile mass remains in the horizontal plane during the actuating movement.

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Limbiate, Italy

Luca Giuseppe Falorni