Physical quantity detection element, physical quantity detection device, electronic apparatus, and moving object

Patent metadata

Field	Value
Publication number	US-9939457-B2
Application number	US-201414504894-A
Country	US
Kind code	B2
Filing date	Oct 2, 2014
Priority date	Oct 3, 2013
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A physical quantity detection element includes: a substrate; first and second fixed electrode portions on the substrate; a movable body on the upper portion of the substrate; and a beam on the movable body, the movable body includes a first movable body on a first side of the beam, and a second movable body on a second side of the beam, the first movable body includes a first movable electrode portion facing the first fixed electrode portion and a first mass portion disposed in an opposite direction of the beam from the first movable electrode portion, the second movable body includes a second movable electrode portion facing the second fixed electrode portion, a mass of the first movable body is greater than a mass of the second movable body, and a mass of the first mass portion is greater than a mass of the first movable electrode portion.

First claim

What is claimed is:

1. A physical quantity detection element comprising:
a substrate;
a first fixed electrode and a second fixed electrode that are provided on a main surface of the substrate, a first side of the first fixed electrode being directly adjacent to a second side of the second fixed electrode, a center area of the substrate being laterally sandwiched by the first side and the second side in a plan view;
a first support that continuously upwardly extends from the main surface of the substrate;
a second support that is different from the first support and that continuously upwardly extends from the main surface of the substrate, the first and second supports being located between the first and second fixed electrodes in the plan view;
a movable body that is provided above the main surface of the substrate; and
a beam that interconnects the first support, the second support and the movable body so that the movable body is supported by the first support, the second support and the beam, a center of the beam being located between the first support and the second support in the plan view so that the center of the beam is spaced apart from the first and second supports in the plan view, the movable body moving with respect to the center of the beam relative to the main surface of the substrate,
wherein the first support and the second support are located directly adjacent to a center of the center area of the substrate in the plan view, and the first support and the second support are spaced apart from the center of the center area in the plan view,
wherein the movable body includes a first movable body on a first side with respect to the center of the beam, and the movable body includes a second movable body on a second side with respect to the center of the beam,
the first movable body includes a first movable electrode facing the first fixed electrode, and the first movable body includes a first mass that extends from an end of the first movable electrode in a first direction away from the beam in the plan view,
the second movable body includes a second movable electrode facing the second fixed electrode,
a mass of the first movable body is greater than a mass of the second movable body,
a mass of the first mass is greater than a mass of the first movable electrode,
wherein the beam is spaced apart from the main surface of the substrate,
wherein, when the movable body is divided into two by a center line in the first direction at an area ratio, masses of the divided portions are equivalent to each other, and
the center line passes through the center of the beam, the first support and the second support in the plan view.

2. The physical quantity detection element according to claim 1 ,
wherein a thickness of the first mass is equivalent to a thickness of the first movable electrode.

3. The physical quantity detection element according to claim 1 ,
wherein a thickness of the first mass is greater than a thickness of the first movable electrode and a thickness of the second movable electrode.

4. The physical quantity detection element according to claim 2 ,
wherein a plurality of first penetration holes are provided in the first movable electrode, and a plurality of second penetration holes are provided in the first mass, and
an average dimension of gaps between the second penetration holes adjacent to each other in the first direction is greater than an average dimension of gaps between the first penetration holes adjacent to each other in the first direction.

5. The physical quantity detection element according to claim 2 ,
wherein a plurality of first penetration holes are provided in the first movable electrode, and a plurality of second penetration holes are provided in the first mass, and
an average dimension of gaps between the second penetration holes adjacent to each other in a second direction perpendicular to the first direction is greater than an average dimension of gaps between the first penetration holes adjacent to each other in the second direction.

6. The physical quantity detection element according to claim 1 ,
wherein buffers are provided on a surface of the first mass facing the substrate.

7. The physical quantity detection element according to claim 1 ,
wherein an electrode is provided on a surface of the first mass facing the substrate.

8. A physical quantity detection device comprising:
the physical quantity detection element according to claim 1 ; and
a detection circuit which outputs a signal according to physical quantity applied to the physical quantity detection element.

9. An electronic apparatus comprising the physical quantity detection element according to claim 1 .

10. A moving object comprising the physical quantity detection element according to claim 1 .

11. A physical quantity detection element comprising:
a substrate;
a first fixed electrode and a second fixed electrode that are provided on a main surface of the substrate, a first side of the first fixed electrode being directly adjacent to a second side of the second fixed electrode, a center area of the substrate being laterally sandwiched by the first side and the second side in a plan view;
a first support that continuously upwardly extends from the main surface of the substrate;
a second support that is different from the first support and that continuously upwardly extends from the main surface of the substrate, the first and second supports being located between the first and second fixed electrodes in the plan view;
a movable body that is provided above the main surface of the substrate; and
a beam that interconnects the first support, the second support and the movable body so that the movable body is supported by the first support, the second support and the beam, a center of the beam being located between the first support and the second support in the plan view so that the center of the beam is spaced apart from the first and second supports in the plan view, the movable body moving with respect to the center of the beam relative to the main surface of the substrate,
wherein the first support and the second support are located directly adjacent to a center of the center area of the substrate in the plan view, and the first support and the second support are spaced apart from the center of the center area in the plan view,
wherein the movable body includes a first movable body on a first side with respect to the center of the beam, and the movable body includes a second movable body on a second side with respect to the center of the beam,
the first movable body includes a first movable electrode facing the first fixed electrode, and the first movable body includes a first mass that extends from an end of the first movable electrode in a first direction away from the beam in the plan view,
the second movable body includes a second movable electrode facing the second fixed electrode,
a mass of the first movable body is greater than a mass of the second movable body,
a mass of the first mass is greater than a mass of the first movable electrode,
wherein the beam is spaced apart from the main surface of the substrate,
wherein the movable body is provided line-symmetrically with respect to a center line in the first direction, and
the center line passes through the center of the beam, the first support and the second support in the plan view.

12. The physical quantity detection element according to claim 11 ,
wherein a thickness of the first mass is equivalent to a thickness of the first movable electrode.

13. The physical quantity detection element according to claim 11 ,
wherein a thickness of t

Assignees

• Seiko Epson Corp

Inventors

• Kigure Shota

Classifications

• G01P15/125 Primary

  by capacitive pick-up · CPC title

• G01P2015/0831

  the mass being of the paddle type having the pivot axis between the longitudinal ends of the mass, e.g. see-saw configuration · CPC title

• G01P2015/0874

  using means for preventing stiction of the seismic mass to the substrate · CPC title

• G01P1/003

  used for damping · CPC title

• G01P2015/0871

  using stopper structures for limiting the travel of the seismic mass · CPC title