A vibration element includes a vibrating part, and a support part which is coupled to the vibrating part to support the vibrating part, wherein the vibrating part and the support part have a first surface and a second surface having a front and back relationship with the first surface, a first electrode is disposed on the first surface, the first electrode includes a first layer as a foundation layer, and a second layer as an upper layer of the first layer, when performing zoning into a first area where the first electrode is not disposed, a second area where the first layer and the second layer are stacked on one another, and a third area where the first layer is formed, identification symbols formed of two or more of the first to third areas are disposed, and an identification code formed of a plurality of the identification symbols is provided.

Provided is a method for manufacturing a vibrator element including a first vibration arm and a second vibration arm that each have a first surface and a second surface. The manufacturing method includes a preparation step of preparing a quartz crystal substrate, a first protective film forming step of forming a first protective film on a first substrate surface of the quartz crystal substrate, a first dry etching step of dry etching the quartz 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 quartz crystal substrate, and a second dry etching step of dry etching the quartz crystal substrate via the second protective film. Outer shapes of the first vibration arm and the second vibration arm are formed from the first surface to the second surface in the first dry etching step, and the outer shapes of the first vibration arm and the second vibration arm are not formed in the second dry etching step.

Provided is a method for manufacturing a vibrator element including a first vibration arm and a second vibration arm that each have a first surface and a second surface. The manufacturing method includes a preparation step of preparing a quartz crystal substrate, a first protective film forming step of forming a first protective film on a first substrate surface of the quartz crystal substrate, a first dry etching step of dry etching the quartz 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 quartz crystal substrate, and a second dry etching step of dry etching the quartz crystal substrate via the second protective film. Outer shapes of the first vibration arm and the second vibration arm are formed from the first surface to the second surface in the first dry etching step, and the outer shapes of the first vibration arm and the second vibration arm are not formed in the second dry etching step.

There are provided an excitation electrode, a quartz crystal vibrator element, a quartz crystal vibrator, a sensor, an oscillator, and a method of manufacturing a quartz crystal vibrator element which are not affected by heat in a process or a use environment to surely prevent a frequency fluctuation from occurring, reduction in size of which can be achieved, and which are low in cost and excellent in productivity. The excitation electrodes are disposed on an outer surface of a quartz crystal plate, apply an electrical field for exciting the quartz crystal plate to the quartz crystal plate, have a single layer structure formed of a two-dimensional layered substance, and are used when arranged as a pair so as to be opposed to each other via the quartz crystal plate.

A resonator includes: a resonator element that includes a base portion and a resonating arm; and a base. When n is one natural number of 2 or greater and j is 1 or greater and a natural number which is less than or equal to n, the resonator element performs resonations with n inherent resonation modes. In a relationship between arbitrary integers k.sub.j and resonance frequencies f.sub.j corresponding to the n inherent resonation modes, respectively, when f.sub.1 represents the resonance frequency of the main resonation of the resonator element and a normalized frequency difference Δf is defined by

[00001]$\Delta .Math..Math.f\equiv \left(\frac{\underset{j=2}{\overset{n}{.Math.}}.Math..Math.k_j.Math.f_j}{-k_1}-f_1\right)/f_1,$

a relationship of |Δf|≧0.03 is satisfied. The arbitrary integers k.sub.j satisfy relationships of 3≦Σ.sub.j=1.sup.n|k.sub.j|≦10 and n≦Σ.sub.j=1.sup.n|k.sub.j|. A ratio of an amount of a change in the resonance frequency of the main resonation, to excitation power that electrically excites the main resonation, is 20 [ppm/μW] or higher.

A resonator includes: a resonator element that includes a base portion and a resonating arm; and a base. When n is one natural number of 2 or greater and j is 1 or greater and a natural number which is less than or equal to n, the resonator element performs resonations with n inherent resonation modes. In a relationship between arbitrary integers k.sub.j and resonance frequencies f.sub.j corresponding to the n inherent resonation modes, respectively, when f.sub.1 represents the resonance frequency of the main resonation of the resonator element and a normalized frequency difference Δf is defined by

[00001]$\Delta .Math..Math.f\equiv \left(\frac{\underset{j=2}{\overset{n}{.Math.}}.Math..Math.k_j.Math.f_j}{-k_1}-f_1\right)/f_1,$

a relationship of |Δf|≧0.03 is satisfied. The arbitrary integers k.sub.j satisfy relationships of 3≦Σ.sub.j=1.sup.n|k.sub.j|≦10 and n≦Σ.sub.j=1.sup.n|k.sub.j|. A ratio of an amount of a change in the resonance frequency of the main resonation, to excitation power that electrically excites the main resonation, is 20 [ppm/μW] or higher.

A method for manufacturing a vibrator element includes a first protective film forming step of forming a first protective film on a first substrate surface of a quartz crystal substrate, a first dry etching step of dry etching the quartz crystal substrate from a first substrate surface side to form a first groove and outer shapes of a first and second vibration arms, a second protective film forming step of forming a second protective film on a second substrate surface of the quartz crystal substrate, and a second dry etching step of dry etching the quartz crystal substrate from a second substrate surface side to form a second groove and outer shapes of the first and second vibration arms. In the first dry etching step, the outer shapes of the first and second vibration arms are formed to be closer to the second substrate surface than is a position where a bottom surface of the second groove is formed.

A method for manufacturing a vibrator element includes a first protective film forming step of forming a first protective film on a first substrate surface of a quartz crystal substrate, a first dry etching step of dry etching the quartz crystal substrate from a first substrate surface side to form a first groove and outer shapes of a first and second vibration arms, a second protective film forming step of forming a second protective film on a second substrate surface of the quartz crystal substrate, and a second dry etching step of dry etching the quartz crystal substrate from a second substrate surface side to form a second groove and outer shapes of the first and second vibration arms. In the first dry etching step, the outer shapes of the first and second vibration arms are formed to be closer to the second substrate surface than is a position where a bottom surface of the second groove is formed.

To improve durability against impact, a quartz crystal resonator element includes a recess in a plan view. The quartz crystal resonator element further includes a first principal surface and a second principal surface that are front and rear surfaces facing away from each other and a side surface disposed between the first principal surface and the second principal surface, and the side surface is formed of flat surfaces and curved surfaces formed by dry etching and alternately arranged. The quartz crystal resonator element preferably has a base and at least one resonating arm extending from the base.

To improve durability against impact, a quartz crystal resonator element includes a recess in a plan view. The quartz crystal resonator element further includes a first principal surface and a second principal surface that are front and rear surfaces facing away from each other and a side surface disposed between the first principal surface and the second principal surface, and the side surface is formed of flat surfaces and curved surfaces formed by dry etching and alternately arranged. The quartz crystal resonator element preferably has a base and at least one resonating arm extending from the base.