A vibration element includes: a base; a first arm continuous with the base; a second arm that is continuous with the base and is adjacent to the first arm; a first electrode disposed on the first arm, the second arm, and the base; a first piezoelectric layer that has a first polarity and that is disposed on the first electrode on the first arm; a second piezoelectric layer that has a second polarity different from the first polarity and that is disposed on the first electrode on the second arm; an insulating layer disposed on the first electrode on the base; and a second electrode disposed on the first piezoelectric layer, the second piezoelectric layer, and the insulating layer.

A vibration element includes: a base; a first arm continuous with the base; a second arm that is continuous with the base and is adjacent to the first arm; a first electrode disposed on the first arm, the second arm, and the base; a first piezoelectric layer that has a first polarity and that is disposed on the first electrode on the first arm; a second piezoelectric layer that has a second polarity different from the first polarity and that is disposed on the first electrode on the second arm; an insulating layer disposed on the first electrode on the base; and a second electrode disposed on the first piezoelectric layer, the second piezoelectric layer, and the insulating layer.

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 method of manufacturing a vibration element includes: a protective film forming step of forming a protective film on a first substrate surface of a crystal substrate; and a dry etching step of dry-etching the crystal substrate via the protective film. The protective film satisfies a relationship of T1<T2<T3, in which T1 is a thickness of the protective film in an inter-arm region positioned between a first vibration arm forming region in which a first vibration arm is formed and a second vibration arm forming region in which a second vibration arm is formed, T2 is a thickness of the protective film in a groove forming region in which a groove is formed, and T3 is a thickness of the protective film in a region of the first vibration arm forming region and the second vibration arm forming region excluding the groove forming region.

A method of manufacturing a vibration element includes: a first protective film forming step of forming a first protective film on a first substrate surface of a crystal substrate; a first dry etching step of dry-etching the crystal substrate via the first protective film; a second protective film forming step of forming a second protective film on a second substrate surface of the crystal substrate; and a second dry etching step of dry-etching the crystal substrate via the second protective film. A relationship of T1<T2<T3 or T4<T5<T6 is satisfied, in which T1 and T4 are thicknesses of the first and second protective films in an inter-arm region, respectively, T2 and T5 are thicknesses of the first and second protective films in first and second groove forming regions, respectively, and T3 and T6 are thicknesses of the first and second protective films in first and second bank portion forming regions, respectively.

A method for manufacturing a vibration element includes, a base film forming step of forming a first base film at a first substrate surface of a quartz crystal substrate in first and second vibrating arm forming regions, a protective film forming step of forming a first protective film in a bank portion forming region of the first base film, and a dry-etching step of dry-etching the quartz crystal substrate through the first base film and the first protective film.

A vibrator device includes a vibrating body having a first surface, a package having a second surface opposed to the first surface of the vibrating body, a circuit board provided to the package so as to be opposed to the first surface of the vibrating body, a plurality of coupling electrodes provided to the first surface of the vibrating body, a first coupling line provided to the second surface of the package, a second coupling line provided to the circuit board, and a bonding material electrically coupling the coupling electrode and the first coupling line to each other, wherein the vibrating body has a protrusion protruding toward the package farther than the coupling electrode at the first surface side, and the protrusion has contact with the second surface of the package.

A vibrator device includes a vibrating body having a first surface, a package having a second surface opposed to the first surface of the vibrating body, a circuit board provided to the package so as to be opposed to the first surface of the vibrating body, a plurality of coupling electrodes provided to the first surface of the vibrating body, a first coupling line provided to the second surface of the package, a second coupling line provided to the circuit board, and a bonding material electrically coupling the coupling electrode and the first coupling line to each other, wherein the vibrating body has a protrusion protruding toward the package farther than the coupling electrode at the first surface side, and the protrusion has contact with the second surface of the package.

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.