Embodiments for modifying a spring mass configuration are disclosed that minimize the effects of unwanted nonlinear motion on a MEMS sensor. The modifications include any or any combination of providing a rigid element between rotating structures of the spring mass configuration, tuning a spring system between the rotating structures and coupling an electrical cancellation system to the rotating structures. In so doing unwanted nonlinear motion such as unwanted 2nd harmonic motion is minimized.

A gyro sensor includes: a substrate; a fixed portion that is fixed to the substrate; a driving portion that is driven in a first direction oriented along a first axis; a mass portion that is connected to the driving portion and is displaced in the first direction; and an elastic portion that is connected to the mass portion and the fixed portion. The mass portion includes a detection portion that is displaceable in a second direction oriented along a second axis orthogonal to the first axis by a Coriolis force to act. An outer circumference surface of the elastic portion includes a main surface, a side surface, and a connection surface connecting the main surface to the side surface. The connection surface has a curved surface portion with a curved surface shape.

A gyro sensor includes: a substrate; a fixed portion that is fixed to the substrate; a driving portion that is driven in a first direction oriented along a first axis; a mass portion that is connected to the driving portion and is displaced in the first direction; and an elastic portion that is connected to the mass portion and the fixed portion. The mass portion includes a detection portion that is displaceable in a second direction oriented along a second axis orthogonal to the first axis by a Coriolis force to act. An outer circumference surface of the elastic portion includes a main surface, a side surface, and a connection surface connecting the main surface to the side surface. The connection surface has a curved surface portion with a curved surface shape.

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.

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.

A rotation rate sensor. The rotation rate sensor includes a substrate having a main extension plane, and includes at least one mass oscillator. The mass oscillator is connected to a drive structure via one or more spring elements and can be excited to oscillate in an excitation direction running in parallel with the main extension plane. The rotation rate sensor has at least one detection element connected to the mass oscillator and a first and second anchor element connected fixedly to the substrate. The detection element is connected to the first anchor element via a first spring element and is connected to the second anchor element via a second spring element. The detection element can be deflected along a detection direction running in parallel with the main extension plane and perpendicularly to the excitation direction. The first and the second spring element comprise a parallelogram spring element.

A rotation rate sensor. The rotation rate sensor includes a substrate having a main extension plane, and includes at least one mass oscillator. The mass oscillator is connected to a drive structure via one or more spring elements and can be excited to oscillate in an excitation direction running in parallel with the main extension plane. The rotation rate sensor has at least one detection element connected to the mass oscillator and a first and second anchor element connected fixedly to the substrate. The detection element is connected to the first anchor element via a first spring element and is connected to the second anchor element via a second spring element. The detection element can be deflected along a detection direction running in parallel with the main extension plane and perpendicularly to the excitation direction. The first and the second spring element comprise a parallelogram spring element.

Test method of a vibrational MEMS structure wherein, a direct, variable modification voltage is applied to a resonance modification test structure having non-rectilinear electrodes, modifying the resonance frequency of the movable mass and the driving frequency. During the test, the movable mass is verified about stability and, if not stable, the vibrational MEMS structure is rejected.

Test method of a vibrational MEMS structure wherein, a direct, variable modification voltage is applied to a resonance modification test structure having non-rectilinear electrodes, modifying the resonance frequency of the movable mass and the driving frequency. During the test, the movable mass is verified about stability and, if not stable, the vibrational MEMS structure is rejected.

Embodiments for modifying a spring mass configuration are disclosed that minimize the effects of unwanted nonlinear motion on a MEMS sensor. The modifications include any or any combination of providing a rigid element between rotating structures of the spring mass configuration, tuning a spring system between the rotating structures and coupling an electrical cancellation system to the rotating structures. In so doing unwanted nonlinear motion such as unwanted 2.sup.nd harmonic motion is minimized.