BULK ACOUSTIC RESONATOR HAVING ELECTRODE HAVING GAP LAYER AND TEMPERATURE COMPENSATION LAYER, FILTER, AND ELECTRONIC APPARATUS

摘要

The present invention relates to a bulk acoustic resonator, comprising: a substrate; an acoustic mirror; a bottom electrode; a top electrode; and a piezoelectric layer disposed between the bottom electrode and the top electrode, wherein the bottom electrode and/or the top electrode is a gap electrode having at least one gap layer, and in a thickness direction of the gap electrode, the gap layer remains at a distance from each of a top surface and a bottom surface of the gap electrode; and a temperature compensation layer made of a material having a temperature coefficient opposite to a temperature coefficient of a material used to form the piezoelectric layer, the temperature compensation layer being provided in a sandwich structure of the resonator composed of the bottom electrode, the piezoelectric layer and the top electrode. The present invention further relates to a filter having the above resonator and an electronic apparatus having the filter or the resonator.