| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a thin-film bulk wave resonator suitable to adjust a resonance frequency and an anti-resonant frequency. <P>SOLUTION: A protecting film 60 is formed on an upper electrode 50B of a parallel arm resonator 10B, and a plurality of apertures are formed in a mesh-like fashion on the protecting film 60 by dry etching to expose a part of the upper electrode 50B. By adjusting the aperture ratio of the protecting film 60, the anti-resonant frequency of the parallel arm resonator 10B can be matched with the resonance frequency of a serial resonator 10A. Since the protecting film 60 with the plurality of apertures formed in the mesh-like fashion has a facility for adjusting the resonance frequency and the anti-resonant frequency of the parallel arm resonator 10B by its weight, the protecting film and a frequency regulation film are formed by one manufacturing process. <P>COPYRIGHT: (C)2009,JPO&INPIT |
