Elastic wave device with integrated inductor

An elastic wave device comprising:

• a piezoelectric substrate;
• an interdigital transducer (IDT) electrode disposed on an upper surface of the piezoelectric substrate;
• an insulator layer disposed on the upper surface of the piezoelectric substrate, the insulator layer sealing the IDT electrode, the insulator layer including a resin and a filler dispersed in the resin;
• a resin layer, distinct from the insulator layer, disposed on an upper surface of the insulator layer, the resin layer including no filler;
• a first terminal electrode disposed on an upper surface of the resin layer;
• an inductor electrode disposed on the insulator layer and covered by the resin layer, the inductor electrode being located directly under the first terminal electrode and occupying an area inside an outer periphery of the first terminal electrode, the inductor electrode having a first end in electrical communication with the IDT electrode and a second end in electrical communication with the first terminal electrode.

An elastic wave device comprising:

• a piezoelectric substrate;
• an interdigital transducer (IDT) electrode disposed on an upper surface of the piezoelectric substrate;
• an excitation space provided on an upper surface of the IDT electrode;
• an insulator layer disposed on the upper surface of the piezoelectric substrate, the insulator layer sealing the IDT electrode and the excitation space, the insulator layer including a resin and a filler dispersed in the resin;
• a top plate electrode disposed in the insulator layer, the top plate electrode covering the excitation space;
• a resin layer, distinct from the insulator layer, disposed on an upper surface of the insulator layer, the resin layer including no filler;
• a first terminal electrode disposed on an upper surface of the resin layer;
• and
• an inductor electrode disposed on the insulator layer and covered by the resin layer, the inductor electrode having a first end in electrical communication with the IDT electrode and a second end in electrical communication with the first terminal electrode and with the top plate electrode.