Piezoelectric resonator, manufacturing method for the same, piezoelectric filter, manufacturing method for the same, duplexer, and electronic communication device

摘要

A piezoelectric resonator includes a substrate (2) and a plurality of vibrating portions (4,5) constructed such that a thin film portion having a piezoelectric thin film (14) of one or more layers is sandwiched by at least a pair of upper electrodes (11,12) and a lower electrode (13), which are opposed to each other, on the upper and lower surfaces of the thin film portion. The vibrating portions (4,5) are separated by at least a distance equal to about »/2, where » represents the vibration wavelength, from elements affecting the vibration characteristics.