Patent ID: 7112913

Claim:
A surface acoustic wave apparatus, comprising: a piezoelectric substrate; at least one electrode for a surface acoustic wave element disposed on the piezoelectric substrate; an electrode pad disposed on the piezoelectric substrate and arranged to be joined with a bump during a bump bonding process performed by a flip chip bonding system; and a wiring electrode for electrically connecting the electrode pad and the electrode for surface acoustic wave element; wherein the electrode pad includes a first electrode layer disposed on the plezoelectric substrate and a second electrode layer laminated on the first electrode layer, the first electrode layer including an etched metal film, and the at least one electrode for the surface acoustic wave element including a material formed by a lift-off process; and a particle size of a conductive particle in the conductive film constituting the second electrode layer and the wiring electrode is smaller than a particle diameter of a conductive particle in one of the electrode for the surface acoustic wave element and the first electrode layer of the electrode pad, which has a smaller film thickness.