A sensor element includes a piezoelectric body and a plurality of electrodes. The piezoelectric body, when viewed on a plane, includes a base part and at least one arm part extending from the base part. The plurality of electrodes are located on a surface of the arm part. The piezoelectric body, when viewed on the plane, further includes a frame part which surrounds the base part and the at least one arm part and upon which the base part is bridged.

A method for manufacturing a vibration element including a first protective film formation step of forming a first protective film, a first dry etching step of performing dry etching via the first protective film to form first grooves and the outer shapes of vibrating arms, a second protective film formation step of forming a second protective film in the first grooves, a second dry etching step of performing dry etching via the second protective film, a third protective film formation step of forming a third protective film, a third dry etching step of performing dry etching via the third protective film to form second grooves and the outer shapes of the vibrating arms, a fourth protective film formation step of forming a fourth protective film in the second grooves, and a fourth dry etching step of performing dry etching via the fourth protective film.

A proof mass assembly includes a monolithic substrate, the monolithic substrate including a proof mass, a proof mass support, and a flexure connecting the proof mass to the proof mass support. The proof mass is configured to rotate relative to the proof mass support via the flexure. The monolithic substrate further includes a first resonator connected to a first major surface of the proof mass and a first major surface of the proof mass support and a second resonator connected to a second major surface of the proof mass and a second major surface of the proof mass support.

A vibration element includes a base and a vibrating arm extending from the base. The vibrating arm includes an arm positioned between the base and a weight. A weight film is disposed on the weight. The weight has a first principal surface and a second principal surface in a front and back relationship with respect to a center plane of the arm. A center of gravity of the weight is located between the first principal surface and the center plane of the arm. A center of gravity of the weight film is located between the second principal surface and the center plane of the arm.

A vibration element includes a base and a vibrating arm extending from the base. The vibrating arm includes an arm positioned between the base and a weight. A weight film is disposed on the weight. The weight has a first principal surface and a second principal surface in a front and back relationship with respect to a center plane of the arm. A center of gravity of the weight is located between the first principal surface and the center plane of the arm. A center of gravity of the weight film is located between the second principal surface and the center plane of the arm.

A piezoelectric body of a sensor includes a driving arm and detecting arm which extend from a base part in a y-axis direction. Excitation electrodes vibrate the driving arm in an x-axis direction. Detecting electrodes enable detection of a signal due to deformation in a z-axis direction of the detecting arm. The piezoelectric body has anisotropy causing vibration of torsional deformation when the driving arm vibrates in the x-axis direction. When the driving arm bends to a +x side, the base part flexes so that a connection position in the base part is displaced to one side in the z-axis direction. The cross-section of the driving arm perpendicular to the y-axis direction causes a bending stiffness to the +x side and to the other side in the z-axis direction is smaller than a bending stiffness to the +x side and to the one side in the z-axis direction.

A piezoelectric body of a sensor includes a driving arm and detecting arm which extend from a base part in a y-axis direction. Excitation electrodes vibrate the driving arm in an x-axis direction. Detecting electrodes enable detection of a signal due to deformation in a z-axis direction of the detecting arm. The piezoelectric body has anisotropy causing vibration of torsional deformation when the driving arm vibrates in the x-axis direction. When the driving arm bends to a +x side, the base part flexes so that a connection position in the base part is displaced to one side in the z-axis direction. The cross-section of the driving arm perpendicular to the y-axis direction causes a bending stiffness to the +x side and to the other side in the z-axis direction is smaller than a bending stiffness to the +x side and to the one side in the z-axis direction.

A sensor element of an angular velocity sensor includes a piezoelectric body, a plurality of excitation electrodes, and a plurality of detection electrodes. The piezoelectric body includes at least two driving arms and a detection arm. The plurality of excitation electrodes excites the two driving arms in phases that are opposite to each other in an x-axis direction. The plurality of detection electrodes takes out a signal that is produced by vibration of the detection arm in the x-axis direction or a z-axis direction. The piezoelectric body further includes a frame portion, a retention portion that extends outward from the frame portion and that supports the frame portion, and a supporting portion that is connected to a side of the retention portion opposite to the frame portion. The two driving arms and the detection arm extend from the frame portion.

A sensor element of an angular velocity sensor includes a piezoelectric body, a plurality of excitation electrodes, and a plurality of detection electrodes. The piezoelectric body includes at least two driving arms and a detection arm. The plurality of excitation electrodes excites the two driving arms in phases that are opposite to each other in an x-axis direction. The plurality of detection electrodes takes out a signal that is produced by vibration of the detection arm in the x-axis direction or a z-axis direction. The piezoelectric body further includes a frame portion, a retention portion that extends outward from the frame portion and that supports the frame portion, and a supporting portion that is connected to a side of the retention portion opposite to the frame portion. The two driving arms and the detection arm extend from the frame portion.

A vibrator device includes a vibrator element, and a support substrate configured to support the vibrator element. The vibrator element includes a drive arm provided with a drive signal electrode and a drive constant-potential electrode, and a detection arm provided with a detection signal electrode and a detection constant-potential electrode. The support substrate includes a base, and a drive signal interconnection electrically coupled to the drive signal electrode, a drive constant-potential interconnection electrically coupled to the drive constant-potential electrode, and a detection signal interconnection electrically coupled to the detection signal electrode all provided to the base, and the drive arm includes a first surface located at the support substrate side, and a second surface located at an opposite side to the first surface. Further, the drive constant-potential electrode is disposed on the first surface, and the drive signal electrode is disposed on the second surface.