摘要 |
A coupled FBAR filter 100 includes first and second input/output vibration portions 110 and 111 respectively including first and second lower electrodes 104 and 106 , first and second upper electrodes 105 and 107 , and a piezoelectric thin film 103 interposed therebetween; and a cavity 102 for commonly guaranteeing vibrations of the first and second input/output vibration portions 110 and 111 so as to couple the vibrations. The first and second input/output vibration portions 110 and 111 are located adjacently in contact with each other with a step therebetween, such that the first and second lower electrodes 104 and 106 are not electrically connected to each other and such that the first and second upper electrodes 105 and 107 are not electrically connected to each other. Insulators 108 and 109 are provided in the vicinity of the step.
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