Abstract: A surface acoustic wave element includes a surface acoustic wave substrate, an interdigital transducer electrode provided on the surface acoustic wave substrate and a lead electrode provided on the surface acoustic wave substrate. The lead electrode is connected to the interdigital transducer electrode. The surface acoustic wave element further includes a bump electrode provided on a portion of the lead electrodes. The bump electrode includes a first electrode structure and a second electrode structure. The first electrode structure has a top surface and is arranged in contact with the lead electrode, and 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 an entire periphery of the top surface of the first electrode structure.

Abstract: A 1-port type surface acoustic wave device can be produced by using the same tools as used for the production of a 2-port type surface acoustic wave device and achieves a substantial improvement in terms of impact resistance. A 1-port surface acoustic wave resonator includes a surface acoustic wave substrate, two dummy bump electrodes and two input/output bump electrodes disposed on the surface acoustic wave substrate adjacent to a plurality of input/output extraction electrodes.

Abstract: A SAW device (11) includes a SAW element (13) which is bonded onto a support substrate (12) in a face down mode through solder (19, 20), and a metal cap (21) enclosing the SAW element (13). Assuming that and .alpha..sub.1, .alpha..sub.2 and .alpha..sub.3 represent the thermal expansion coefficients of the SAW element (13), the support substrate (12) and the conductive cap (21) along the surface wave propagation direction respectively, .alpha..sub.3 .ltoreq..alpha..sub.1 when .alpha..sub.1 >.alpha..sub.2, and .alpha..sub.3 .ltoreq..alpha..sub.1 when .alpha..sub.1 <.alpha..sub.2.