Double film bulk acoustic resonator having electrode edge alignments providing improved quality factor or electromechanical coupling coefficient

A device, comprising:

• a first terminal;
• a first acoustic resonator comprising a first electrode, a second electrode, and a first piezoelectric layer extending between the first and second electrodes;
• a second acoustic resonator comprising the second electrode, a third electrode, and a second piezoelectric layer extending between the second and third electrodes;
• and
• a second terminal,
• wherein the first terminal is connected to the first and third electrodes and the second terminal is connected to the second electrode such that the first and second acoustic resonators are configured to operate in parallel with each other, and
• wherein the first through third electrodes each have lateral edges that are offset from lateral edges of the other electrodes and the first, second, and third electrodes have lateral edges defining one of a Δ configuration, a ∇ configuration, or a Ξ configuration.

An acoustic resonator, comprising:

• a substrate having a trench with lateral boundaries;
• a first electrode formed on the substrate over the trench and having lateral edges that are laterally offset from the lateral boundaries of the trench by a first distance;
• a first piezoelectric layer formed on the first electrode;
• a second electrode formed on the first piezoelectric layer and having edges that are laterally aligned inside the lateral boundaries of the trench;
• a second piezoelectric layer located on the second electrode;
• and
• a third electrode located on the second piezoelectric layer and having edges that are laterally offset from the edges of the second electrode by a second distance greater than or equal to approximately 0.5% of a width of the trench.