RESONATOR ELEMENT, RESONATOR, ELECTRONIC DEVICE AND ELECTRONIC APPARATUS

• US 20130249353A1
• Filed: 03/18/2013
• Published: 09/26/2013
• Est. Priority Date: 03/21/2012
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: NAITO, Matsutaro, II, Toshihiro, Endo, Hideo
• Granted Patent: US 9,496,480 B2
• Time in Patent Office: Days
• US Class Current: 310/367
• CPC Class Codes: H03H 9/02023 consisting of quartz
• CPC Class Codes: H03H 9/02157 Dimensional parameters, e.g. ratio between two dimension parameters, length, width or thickness
• CPC Class Codes: H03H 9/0519 for cantilever H03H9/1021 takes precedence
• CPC Class Codes: H03H 9/0542 consisting of a lateral arrangement H03H9/0566 takes precedence
• CPC Class Codes: H03H 9/0552 the device and the other elements being mounted on opposite sides of a common substrate
• CPC Class Codes: H03H 9/1021 the BAW device being of the cantilever type
• CPC Class Codes: H03H 9/177 of the energy-trap type
• CPC Class Codes: H03H 9/19 consisting of quartz
• CPC Class Codes: H10N 30/101 with electrical and mechanical input and output, e.g. having combined actuator and sensor parts

Abstract

When a size from a main surface of an outer edge to a step of a first stage of a vibration section is Md1, a size from the step of the first stage to a step of a second stage is Md2, a density of materials of the substrate is d_A, a density of materials of the excitation electrode is d_B, and a thickness of the excitation electrode on a main surface of a mesa of the second stage is t_B, a relationship of ((Md2+(d_B/d_A)×t_B))/Md1≦1.4 is satisfied.

Claims

1. A resonator element comprising:

a substrate including a vibration section that vibrates in a thickness shear vibration mode and has a step on a side surface, and an outer edge that is disposed along an outer edge of the vibration section and has a thickness thinner than that of the vibration section; and

an excitation electrode that is disposed on the vibration section,

wherein when a size from a main surface of the outer edge to a step of a first stage of the vibration section is Md1, a size from the step of the first stage to a step of a second stage is Md2, a density of materials of the substrate is d_A, a density of materials of the excitation electrode is d_B, and a thickness of the excitation electrode on a main surface of a mesa of the second stage is t_B, a relationship of ((Md2+(d_B/d_A)×

t_B))/Md1≦

1.4 is satisfied.

2. The resonator element according to claim 1, wherein a relationship of 0.5≦

((Md2+(d_B/d_A)×

t_B))/Md1≦

1.4 is satisfied.

3. The resonator element according to claim 1, wherein the substrate is a rotated Y-cut quartz crystal substrate.

4. The resonator element according to claim 1, wherein an outer shape of the vibration section is a rectangular shape in plan view, and

a length along a vibration direction of the thickness shear vibration of the first stage of the vibration section is longer than the length along a vibrating direction of the thickness shear vibration of the second stage of the vibration section.

5. The resonator element according to claim 1, wherein an outer shape of the excitation electrode is the same as the outer shape of the second stage of the vibration section in plan view.

6. A resonator comprising:

a resonator element according to claim 1; and

a package accommodating the resonator element.

7. A resonator comprising:

a resonator element according to claim 2; and

a package accommodating the resonator element.

8. An electronic device comprising:

the resonator element according to claim 1; and

an electronic element.

9. An electronic device comprising:

the resonator element according to claim 2; and

an electronic element.

10. An electronic apparatus comprising:

a resonator element according to claim 1.

11. An electronic apparatus comprising:

a resonator element according to claim 2.