Patent ID: 6785117
Filing Date: 2004-08-31
Classification: G01P

Abstract:
A capacitive device comprising:a substrate; a movable electrode, which is located above a surface of the substrate and is movable with respect to the substrate along directions that are substantially orthogonal to the surface, wherein the movable electrode includes a substrate-confronting surface, at which the movable electrode confronts the surface of the substrate, and an electrode-confronting surface; and a fixed electrode, which is stationary with respect to the substrate, wherein the fixed electrode includes a substrate-confronting surface, at which the fixed electrode confronts the surface of the substrate, and an electrode-confronting surface, wherein the substrate-confronting surfaces are substantially parallel to the surface of the substrate, wherein the substrate-confronting surfaces are substantially planar and substantially at the same level along the directions that are substantially orthogonal to the surface of the substrate before the movable electrode is displaced, wherein the electrode-confronting surfaces confront each other and are substantially orthogonal to the surface of the substrate, wherein when the movable electrode is displaced in a first direction that is substantially orthogonal to the surface of the substrate, the total sum of area-distance quotients in an overlap between the electrode-confronting surfaces remains substantially unchanged or decreases to provide a first reduction rate that is substantially zero or more, wherein when the movable electrode is displaced in a second direction that is substantially opposite to the first direction, the total sum of area-distance quotients remains substantially unchanged or decreases to provide a second reduction rate that is substantially zero or more, and wherein the reduction rates are different from each other.