Piezoelectric thin film resonator, filter, and duplexer including a film inserted into the piezoelectric film

摘要

A piezoelectric thin film resonator includes: a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode facing each other across at least a part of the piezoelectric film; and an insertion film that is inserted into the piezoelectric film, is located in at least a part of an outer periphery region in a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, and is not located in a center region of the resonance region.

主权项

1. A piezoelectric thin film resonator comprising:
a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode facing each other across at least a part of the piezoelectric film; and an insertion film that is inserted into the piezoelectric film, is located in at least a part of an outer periphery region in a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, and is not located in a center region of the resonance region, wherein the insertion film is located from the at least a part of the outer periphery region to an outside of the resonance region, wherein the insertion film is exposed from a side surface of the piezoelectric film.