| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a piezoelectric thin film resonator in which temperature stability of a resonant frequency is improved without damaging an electromechanical coupling coefficient and an acoustic quality coefficient while effectively utilizing the feature of an AlN thin film that an acoustic wave propagation velocity is high. <P>SOLUTION: A vibrating part 121 is configured while including a part of a piezoelectric layered body structure 14 formed on a substrate 112. The piezoelectric layered body structure 14 is configured by layering a lower electrode 15, a piezoelectric film 16 and an upper electrode 17. The substrate 112 forms a void 120 allowing the vibration of the vibrating part in an area corresponding to the vibrating part 121. The piezoelectric film 16 contains aluminum nitride as a principal component, the lower electrode 15 and the upper electrode 17 contain molybdenum as a principal component, and the vibrating part 121 includes at least a part of an insulating layer 13, bonded to the piezoelectric layered body structure 14, containing silicon nitride as a principal component. <P>COPYRIGHT: (C)2008,JPO&INPIT |
