PIEZOELECTRIC THIN FILM RESONATOR, AND FILTER

摘要

PROBLEM TO BE SOLVED: To provide a piezoelectric thin film resonator and a filter that can suppress spuriousness.

SOLUTION: The present invention relates to the piezoelectric thin film resonator having a lower electrode (43) provided to form a gap on a gap (46) of a substrate (41) or with the substrate, a piezoelectric film (44) provided on the lower electrode, an upper electrode (45) provided on the piezoelectric film to have a resonance region (50) opposed to the lower electrode across the piezoelectric film, a support region (52) provided at a periphery of the resonance region, having a width 0.35 to 0.65 time as large as the wavelength of a laterally propagated wave motion, and a peripheral region (54) provided at a periphery of the support region and cutting off the laterally propagated wave motion; and relates to the filter.

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