Electronic device and formation method therefor

A method of forming an electronic device, comprising:

• providing a first wafer and a second wafer, forming a reception cap cavity in a receiving region of the first wafer by etching the first wafer, forming an emitter resonator in an emission region of the first wafer by sequentially forming therein a first electrode, a piezoelectric layer, a second electrode and a passivation layer, forming an emitter cap cavity in an emission region of the second wafer by etching the second wafer, and forming a reception resonator in a receiving region of the second wafer by sequentially forming therein a first electrode, a piezoelectric layer, a second electrode and a passivation layer;
• and
• bonding together the first and second wafers so that the reception cap cavity in the first wafer sealingly closes the reception resonator on the second wafer to form a reception filter and that the emitter cap cavity in the second wafer sealingly closes the emitter resonator on the first wafer to form an emitter filter,
• wherein a first hollow cavity is further formed in the emission region of the first wafer, and the emitter filter comprising the first hollow cavity, the emitter resonator and the emitter cap cavity, which are arranged in a direction pointing from the first wafer to the second wafer, and
• wherein a second hollow cavity is further formed in the receiving region of the second wafer, the reception filter comprising the second hollow cavity, the reception resonator and the reception cap cavity, which are arranged in a direction pointing from the second wafer to the first wafer, and wherein the reception filter is inverted relative to the emitter filter.