| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a BAW filter capable of improving a mechanical quality factor of each resonator and filter characteristics, and to provide a method of manufacturing the BAW filter. <P>SOLUTION: In the BAW filter, a plurality of resonators 3, which have a piezoelectric layer 32 between lower and upper electrodes 31, 33, are formed at one surface side of a support substrate 1. On the support substrate 1, a cavity 1a, which exposes a surface at the side of the support substrate 1 in the lower electrode 31 of each resonator 3, is formed. Each resonator 3 is formed while warping in a convex shape at the side of the support substrate 1, and a surface 31a at the side of the cavity 1a in the lower electrode 31 becomes a convex curved surface. <P>COPYRIGHT: (C)2010,JPO&INPIT |
