ELECTROSTATIC CAPACITANCE SENSOR

• US 20130229193A1
• Filed: 03/01/2013
• Published: 09/05/2013
• Est. Priority Date: 03/02/2012
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: UEDA, Hideki, MORI, Takeshi, KAKIMOTO, Katsumi, YOSHIDA, Hitoshi, IBARA, Nobuyuki, KISHIMOTO, Shinichi, OKADA, Takeshi, NOMURA, Masatoshi, OGIHARA, Jun
• Granted Patent: US 9,274,153 B2
• Time in Patent Office: Days
• US Class Current: 324/661
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 3/0086 Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24

Abstract

An electrostatic capacitance sensor 1 includes a semiconductor substrate 4. A first fixing plate 2 is joined to a one-side surface 4a of the semiconductor substrate 4, and a second fixing plate 3 is joined to other-side surface 4b of the semiconductor substrate 4, whereby a space portion S is formed. Then, static electricity suppressing means 70 for suppressing static electricity from being generated in the space portion S is provided in the electrostatic capacitance sensor 1.

Claims

1. An electrostatic capacitance sensor, including:

a semiconductor substrate in which a movable body having a movable electrode is formed,

a first fixing plate joined to one surface of the semiconductor substrate,

a second fixing plate joined to the other surface of the semiconductor substrate,

a fixed electrode formed on the first fixing plate and arranged opposite to the movable electrode at an interval,

wherein the first fixing plate is joined to one surface of the semiconductor substrate, and the second fixing plate is joined to the other surface of the semiconductor substrate, whereby a space portion is formed,

wherein static electricity suppressing means for suppressing static electricity from being generated in the space portion is provided in the electrostatic capacitance sensor.

2. The electrostatic capacitance sensor according to claim 1, wherein the static electricity suppressing means is a metal film formed on at least one of a spot of an inner surface of the first fixing plate, the spot being other than a spot on which the fixed electrode is formed, and of an inner surface of the second fixing plate, and the metal film is electrically insulated from the fixed electrode, and is electrically connected to the movable body.

3. The electrostatic capacitance sensor according to claim 1, wherein the movable body is formed without using an insulator.

4. The electrostatic capacitance sensor according to claim 2, wherein the metal film is formed on a recessed portion formed on either of the inner surface of the first fixing plate and the inner surface of the second fixing plate.

5. The electrostatic capacitance sensor according to claim 1, wherein the second fixing plate is a conductor.

6. The electrostatic capacitance sensor according to claim 5, wherein a recessed portion is formed on the inner surface of the second fixing plate.

7. The electrostatic capacitance sensor according to claim 1, wherein the static electricity suppressing means is a static electricity suppressing material filled in the space portion.

8. The electrostatic capacitance sensor according to claim 7, wherein the static electricity suppressing material is either of ionized air and inert gas.

9. The electrostatic capacitance sensor according to claim 1, wherein a communication path that allows the space portion to communicate with an outer space is formed in the electrostatic capacitance sensor.