Bulk acoustic wave resonator having a plurality of compensation layers and duplexer using same

A duplexer comprising:

• a phase shifter configured to shift a phase of a received signal, and output the phase-shifted received signal;
• and
• a filter configured to filter the phase-shifted received signal output from the phase shifter, and output the filtered phase-shifted received signal to a receive output of the duplexer;
• wherein the filter comprises a film bulk acoustic source resonator comprising:
• a first electrode,
• a second electrode,
• a piezoelectric layer disposed between the first electrode and the second electrode,
• a compensation layer disposed above the bulk acoustic resonance unit, and
• a property compensation layer disposed above the compensation layer, wherein the property compensation layer is disposed above the edges of a surface of the compensation layer so that a remaining portion of the surface between the edges is not covered by the property compensation layer.