MEMS device

• US 9,550,663 B2
• Filed: 02/03/2014
• Issued: 01/24/2017
• Est. Priority Date: 02/06/2013
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: Goda, Kazuo, Taura, Takumi, Kishimoto, Shinichi, Ueda, Hideki, Mori, Takeshi
• Primary Examiner(s): Toledo, Fernando L
• Assistant Examiner(s): PRASAD, NEIL R
• Application Number:
  US14/764,572
• Publication Number:
  US 20150368089A1
• Time in Patent Office: 1,086 Days
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 3/0008 Structures for avoiding electrostatic attraction, e.g. avoiding charge accumulation
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 2015/0834 the mass constituting a pendulum having the pivot axis disposed symmetrically between the longitudinal ends, the center of mass being shifted away from the plane of the pendulum which includes the pivot axis
• CPC Class Codes: H01L 29/84 controllable by variation of applied mechanical force, e.g. of pressure

Abstract

A MEMS device includes a movable section, a frame, a beam, and an electrode substrate. The frame surrounds a surrounding of the movable section. The beam extends from at least a part of the frame, and is connected to the movable section. The electrode substrate includes a fixed electrode, an extended electrode, and a substrate section. The fixed electrode is formed on the electrode substrate in at least a part of a region facing a swing section. The extended electrode is connected to the fixed electrode, and is formed on the electrode substrate in at least a part of a region facing the shaft.

Claims

1. A MEMS device comprising:

a sensor substrate including a movable section, a beam connected to the movable section, and a frame connected to the beam; and

a substrate including a fixed electrode and an extended electrode, and disposed on the sensor substrate,

wherein the fixed electrode is formed on the substrate in at least a part of a region facing the movable section, and

the extended electrode is connected to the fixed electrode, and formed on the substrate in at least a part of a region facing the beam.

2. The MEMS device of claim 1, wherein

the movable section includes a first portion and a second portion with the beam interposed therebetween,

the fixed electrode includes a first fixed electrode and a second fixed electrode;

the extended electrode includes a first extended electrode and a second extended electrode;

the first fixed electrode is formed in at least a part of a region facing the first portion;

the second fixed electrode is formed in at least a part of a region facing the second portion;

the first extended electrode is connected to the first fixed electrode, and formed on the substrate in at least a part of a region facing the beam, and

the second extended electrode is connected to the second fixed electrode, and formed on the substrate in at least a part of the region facing the beam.

3. The MEMS device of claim 2, wherein the first extended electrode and the second extended electrode are formed point-symmetrically.

4. The MEMS device of claim 2, wherein the first extended electrode and the second extended electrode have a rectangular shape.

5. The MEMS device of claim 2, wherein the movable section includes a recess in at least a part of a region facing a portion interposed between the first fixed electrode and the second fixed electrode.

6. The MEMS device of claim 2, wherein the second portion has an opening at an opposite side to a surface facing the second fixed electrode.

7. The MEMS device of claim 1, wherein the movable section is formed of SOI (Silicon on Insulator).

8. The MEMS device of claim 7, wherein the SOI includes a first Si layer, a second Si layer, and an oxide film between the first Si layer and the second Si layer.

9. The MEMS device of claim 8, wherein the beam is formed of the first Si layer.

10. The MEMS device of claim 1, wherein the frame is formed of Si, and the substrate is formed of glass.

11. The MEMS device of claim 10, wherein the frame and the substrate are bonded to each other by anodic bonding.

12. The MEMS device of claim 1, wherein the fixed electrode is formed of a metal thin film, and connected to a lead electrode formed of Si in the substrate.