PIEZOELECTRIC RESONANCE ELEMENT AND ELECTRONIC APPLIANCE

摘要

PROBLEM TO BE SOLVED: To provide a piezoelectric thin film resonator which is stable in the temperature characteristic of a resonance frequency and is also excellent in anti-resonance characteristic. SOLUTION: A quartz substrate 22 is etched from the side of a rear surface to form a cavity 24 on the rear surface of the substrate 22 and a thin film supporting part 23 consisting of a part of the substrate 22 is formed on its upper surface. A piezoelectric element part 27 consisting of a piezoelectric thin film 25 consisting of PZT, an exciting electrode 26a on the lower surface of the film 25 and an exciting electrode 26b on the upper surface of the film 25 is formed on the upper surface of the part 23.