Acoustic resonator device with at least one air-ring and frame

An acoustic resonator device, comprising:

• a bottom electrode disposed on a substrate over an air cavity;
• a piezoelectric layer disposed on the bottom electrode;
• a top electrode disposed on the piezoelectric layer, an overlap between the top electrode, the piezoelectric layer and the bottom electrode over the air cavity defining a main membrane region;
• at least one air-ring defining an outside boundary of the main membrane region;
• and
• a first frame formed between the substrate and the bottom electrode.

An acoustic resonator device, comprising:

• a bottom electrode disposed on a substrate over an air cavity;
• a piezoelectric layer disposed on the bottom electrode and doped with at least one rare earth element;
• a top electrode disposed on the piezoelectric layer, an overlap between the top electrode, the piezoelectric layer and the bottom electrode over the air cavity defining a main membrane region;
• an air-ring defining a boundary of the main membrane region and located between the piezoelectric layer and the top electrode;
• a first frame formed between the bottom electrode and the piezoelectric layer;
• and
• a second frame formed between the piezoelectric layer and the top electrode,
• wherein an active region is formed within the main membrane region, and a boundary of the active region is defined by at least one of an inner edge of the first frame and an inner edge of the second frame.