| 摘要 |
PURPOSE:To enable the formation of a movable beam in a short time by a method wherein the movable beam of the titled device having a beam structure is put in a triple structure of a poly Si film and members formed above and below the film which have alkali etching resistance. CONSTITUTION:The movable beam 1 provided on the substrate 9 in the form of a cantilever beam and having the natural frequency is put in a triple structure wherein for example the high concentration P<+> poly Si film 3 of alkali etching resistance constituting an electrode layer is sandwiched with nitride films 5 and 7 of the same property. On the other hand, a P<+> region 13 is formed in the substrate 9 in opposition to the beam 1 via thermal oxide SiO2 film 11, and then made as a fixed electrode layer, resulting in the formation of a capacitor between the Si film 3. Such a triple structure facilitates the manufacture and enables the formation of the movable beam with good accuracy, because of no utilization of anisotropy in etching. |
