| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a BAW resonance device can improve the mechanical quality factor of an entire resonator and achieving ruggedization, and to provide a method of manufacturing the BAW resonance device. <P>SOLUTION: 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 comprising a single crystal substrate. An insulating layer 4 surrounding each resonator 3 is formed. On one surface of the support substrate 1, a plurality of cavities 1a, which expose the lower electrode 31 of the resonator 3 and the insulating layer 4 and have a cross section in an inverted trapezoidal shape, are formed by wet anisotropy etching utilizing crystal orientation dependence of etching speed. In a virtual formation region of a virtual etching hole 40 in the insulating layer 4 when it is assumed that the cavity 1a is formed by the anisotropy etching through one virtual etching hole 40 of the insulating layer 4, a group of a plurality of small etching holes 41 having an opening size smaller than that of the virtual etching hole 40 is formed. <P>COPYRIGHT: (C)2010,JPO&INPIT |
