Patent ID: 7973373

Claim:
A microminiature moving device comprising: stationary parts formed of a single-crystal silicon layer of a silicon-on-insulator (SOI) wafer that comprises a single-crystal silicon substrate, an insulating layer on a surface of the single-crystal silicon substrate, and the single-crystal silicon layer on a surface of the insulating layer and fixed to stationary part fixing areas of the surface of said single-crystal silicon substrate by the insulating layer sandwiched therebetween, so that those surface areas except the stationary part fixing areas of the surface of the single-crystal silicon substrate are exposed; movable elements formed of the single-crystal silicon layer of the silicon-on-insulator wafer and connected at least by one end to one of the stationary parts so as to be moveable in parallel to the surface of the single-crystal silicon substrate; and depressions in all the exposed surface areas of the single-crystal silicon subtrate, wherein: the depressions have edges at the surface of the single-crystal silicon substrate and have a depth greater than the insulating layer thickness; said movable elements are above said depressions and have underside surface areas without the insulating layer thereon that face the single-crystal substrate; the insulating layer sandwiched between the stationary parts and the single-crystal silicon substrate has edges that are indented from the edges of the depressions so that the single-crystal silicon substrate has marginal surface areas extending from the edges of the depressions without the insulating layer thereon and the stationary parts have underside marginal surface areas extending from underside edges thereof without the insulating layer thereon that overhang the depressions and further overhang the marginal surface areas of the single-crystal silicon substrate; said stationary parts have pad portions located in an electrode pad forming area; and a metal film is on surface areas and sidewall surface areas of respective pad portions of the stationary parts located in the electrode pad forming area and on surface areas of the depressions between the respective pad portions of the stationary parts located in the electrode pad forming area.