Surface acoustic wave element having a bump electrode and surface acoustic wave device comprising the same

摘要

The surface acoustic wave element (10) comprises a surface acoustic wave substrate (11), interdigital transducer electrode means (12) provided on the surface acoustic wave substrate and a lead electrode means (14) provided on the surface acoustic wave substrate. The lead electrode means are connected to the interdigital transducer electrode. The surface acoustic wave element further comprises bump electrode means (40) provided on a portion of the lead electrodes. The bump electrode means include a first electrode structure (41) and a second electrode structure (42). The first electrode structure has a top surface and is in contact with the lead electrode; the second electrode structure covers a portion of the top surface of the first electrode structure such that the remaining portion of the top surface of the first electrode structure is exposed along substantially the whole periphery of the top surface the first electrode structure.