ACOUSTIC WAVE DEVICE

摘要

In order to minimize the degradation in resonance characteristics, an acoustic wave device is provided with a substrate (10), a piezoelectric thin film (14) disposed on the substrate, a bottom electrode (12) and a top electrode (16) sandwiching at least a portion of the piezoelectric thin film, a resonance region (50) in which the piezoelectric thin film is sandwiched and the bottom electrode and the top electrode are facing one another, a first mass loading film (28) equipped with multiple island patterns in the resonance region, and a second mass loading region (29) equipped with multiple opening patterns disposed in positions corresponding respectively to the multiple island patterns in the resonance region.