Granted Patent B2

US 8,176,782 · App. 12/296,554 · Granted May 15, 2012

Abstract

Claims (6)

1. A capacitive sensor, comprising:

a first detector movably supported by a fixed portion of a semiconductor layer through a beam portion such that an asymmetric weight balance is kept, in which a first movable electrode that moves according to displacement of a physical value in a thickness direction of the semiconductor layer and a first fixed electrode formed on a support substrate that supports the semiconductor layer are opposed to each other with a gap interposed therebetween, the first detector detecting the physical value based on a capacitance detected according to a size of the first movable electrode and the first fixed electrode, the semiconductor layer being a single crystal silicon layer, a movable mechanism of the first movable electrode comprising the fixed portion, the beam portion and the first movable electrode being formed by vertically etching the single crystal silicon layer; and

a second detector having:

a second movable electrode movably supported by the fixed portion of the semiconductor layer through a beam portion, and that is operated according to displacement of physical values in both directions of the semiconductor layer; and

a second fixed electrode formed by the semiconductor layer, wherein the second movable electrode and the second fixed electrode are opposed to each other through a gap, the second detector detecting a physical value based on a capacitance detected according to a size of the gap between the second movable electrode and the second fixed electrode,

wherein the first movable electrode of the first detector has a shape surrounding the second detector.

Assignments (7)