Patent ID: 8384497

Claim:
A piezoelectric resonator structure, comprising: (a) a substrate having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween; (b) an acoustic mirror having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the substrate; (c) a first electrode having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the acoustic mirror; (d) a piezoelectric layer having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the first electrode; (e) a second electrode having a top surface and a bottom surface, a first end portion and an opposite, second end portion, and a body portion defined therebetween, wherein the bottom surface is formed on the top surface of the piezoelectric layer, wherein the overlapped area of body portions of the substrate, the acoustic mirror, the first electrode, the piezoelectric layer and the second electrode is defined as an active area A; and (f) a first interference structure extending from the first end portion of the second electrode to form a first air gap between the first interference structure and the first end portion of the piezoelectric layer, and a second interference structure extending from the second end portion of the second electrode to form a second air gap between the second interference structure and the second end portion of the piezoelectric layer, wherein the first interference structure and the second interference structure are made of a conductive material that is different from that of the second electrode, or a non-conductive material, or a dielectric material.