Film bulk acoustic resonator and film bulk acoustic resonator circuit

摘要

In a film bulk acoustic resonator, a multi-layered member is placed on a substrate. The multi-layered member has: a common electrode; a piezoelectric layer formed on the common electrode; a first electrode which is formed on the piezoelectric layer, and which is used for a resonator; a second electrode which surrounds the edge of the first electrode with forming a gap therebetween, and which is used for a spurious suppressing element; a first wiring through which an electric power is supplied to the first electrode; and a second wiring through which an electric power is supplied to the second electrode. In the film bulk acoustic resonator, the piezoelectric layer includes a ferroelectric film, and a polarization state of the ferroelectric film corresponding to the resonator is different from a polarization state of the ferroelectric film corresponding to the spurious suppressing element.