| 摘要 |
PURPOSE:To obtain an element which operates with high efficiency and has a small temperature coefficient by using a silicon substrate which is cut in a crystal surface equivalent to a (100) surface as a substrate material and forming a zinc oxide film on this silicon substrate, and forming a dielectric film and an electrode in contact with this zinc oxide film. CONSTITUTION:The silicon substrate 5 is cut in the plane equivalent to the (100) surface and the zinc oxide film formed thereupon so that its piezoelectric axis is perpendicular to the surface of the silicon substrate 5 is shown by 6; and the dielectric film 7 formed partially on the surface of the zinc oxide film 6 is made of silicon dioxide and comb-shaped electrodes formed on the surface of the zinc oxide film 6 where the dielectric film 7 is not present are shown by 8 and 9. Further, the zinc oxide film 6 and dielectric film 7 are formed by a sputtering method, CVD method, etc. Further, the comb-shaped electrodes 8 and 9 are formed by vapor-depositing metal such as aluminum. A Sezawa wave is excited as a surface acoustic wave to the input electrode 8 of the element of this structure in a direction equivalent to the (011) axial direction of silicon 5. Consequently, the surface acoustic wave propagates on the surface of the zinc oxide film 6 and reaches the output electrode 9. |
