Resonator element, resonator, resonator device, oscillator, electronic apparatus, and moving object

Patent metadata

Field	Value
Publication number	US-9712110-B2
Application number	US-201615005280-A
Country	US
Kind code	B2
Filing date	Jan 25, 2016
Priority date	Jan 29, 2015
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A resonator element includes a quartz crystal substrate in which a plane including X and Z′ axes is set as a main plane and a direction oriented along a Y′ axis is a thickness direction. The quartz crystal substrate includes a first region in which thickness shear vibration is generated, a second region that has a thickness thinner than the first region, and first protrusions that are disposed between one pair of electrode pads disposed to be lined in a direction oriented along a Z′ axis on a mounted side of the second region. When Lx is a length of the first protrusions along the X axis and λ is a wavelength of flexural vibration of the quartz crystal substrate, a relation of “λ/2×(2n+1)−0.1λ≦Lx≦λ/2×(2n+1)+0.1λ” (where n is a positive integer) is satisfied.

First claim

What is claimed is:

1. A resonator element comprising:
a quartz crystal substrate in which an X axis of an orthogonal coordinate system having the X axis serving as an electric axis, a Y axis serving as a mechanical axis, and a Z axis serving as an optical axis, which are crystallographic axes of quartz crystal, is set as a rotation axis, an axis inclined from the Z axis so that a +Z side is rotated in a −Y direction of the Y axis is set as a Z′ axis, an axis inclined from the Y axis so that a +Y side is rotated in a +Z direction of the Z axis is set as a Y′ axis, a plane including the X and Z′ axes is set as a main plane, and the direction oriented along the Y′ axis is set as a thickness direction; and
a pair of electrode pads,
wherein the quartz crystal substrate includes
a first region in which thickness shear vibration is generated,
a second region that is located in periphery of the first region and has a thickness thinner than the first region, and
a first protrusion that is disposed to be lined with the first region in a direction oriented along the X axis at one end side of the second region along the X axis,

wherein the one pair of electrode pads are disposed to be lined in a direction oriented along the Z′ axis at the one end side of the second region in the direction oriented along the X axis,
wherein the first protrusion is present between the one pair of electrode pads, and
wherein when Lx is a length of the first protrusion along the X axis and λ is a wavelength of flexural vibration generated in the quartz crystal substrate, a relation of “λ/2×(2n+1)−0.1λ≦Lx≦λ/2×(2n+1)+0.1λ” (where n is a positive integer) is satisfied.

2. The resonator element according to claim 1 ,
wherein when Lz is a length of the first protrusion along the Z′ axis and Mz is a length of the first region along the Z′ axis, a relation of “0<Lz/Mz≦0.7” is satisfied.

3. The resonator element according to claim 1 ,
wherein the first protrusion is disposed in a region which vibration displacement energy by the vibration section does not reach.

4. The resonator element according to claim 1 ,
wherein the first protrusion has two side surfaces extending along the Z′ axis, and
wherein of the two side surfaces, one side surface is disposed at a position of one maximum amplitude of the flexural vibration and the other side surface is disposed at a position of the other maximum amplitude of the flexural vibration.

5. The resonator element according to claim 1 , further comprising:
a pair of second protrusions that are disposed to be lined in the direction oriented along the Z′ axis at the other end side of the second region along the X axis.

6. The resonator element according to claim 1 ,
wherein the first region includes
a first portion, and
a second portion that has a thickness thinner than the first portion and is present between the first portion and the second region at least in a vibration direction of the thickness shear vibration in a plan view.

7. The resonator element according to claim 1 , further comprising:
excitation electrodes that are formed in the first and second regions.

8. The resonator element according to claim 2 , further comprising:
excitation electrodes that are formed in the first and second regions.

9. The resonator element according to claim 3 , further comprising:
excitation electrodes that are formed in the first and second regions.

10. The resonator element according to claim 4 , further comprising:
excitation electrodes that are formed in the first and second regions.

11. A resonator comprising:
the resonator element according to claim 1 ; and
a package in which the resonator element is accommodated.

12. A resonator comprising:
the resonator element according to claim 2 ; and
a package in which the resonator element is accommodated.

13. A resonator device comprising:
the resonator element according to claim 1 ; and
an electronic element.

14. A resonator device comprising:
the resonator element according to claim 2 ; and
an electronic element.

15. The resonator device according to claim 13 ,
wherein the electronic element is a thermosensitive element.

16. An oscillator comprising:
the resonator element according to claim 1 ; and
an oscillation circuit that is electrically connected to the resonator element.

17. An oscillator comprising:
the resonator element according to claim 2 ; and
an oscillation circuit that is electrically connected to the resonator element.

18. An electronic apparatus comprising:
the resonator element according to claim 1 .

19. A moving object comprising:
the resonator element according to claim 1 .

Assignees

• Seiko Epson Corp

Inventors

• Yamashita Go

Classifications

• H03H9/177

  of the energy-trap type · CPC title

• H03H2009/02496

  Horizontal, i.e. parallel to the substrate plane · CPC title

• H03H9/02157

  Dimensional parameters, e.g. ratio between two dimension parameters, length, width or thickness · CPC title

• H03H9/19 Primary

  consisting of quartz · CPC title

• H03H9/1021

  the BAW device being of the cantilever type · CPC title