A surface acoustic wave device includes a piezoelectric substrate and an electrode
section, disposed on the piezoelectric substrate, having a thin-film structure.
The electrode section includes interdigital electrodes and junction electrodes
connected to the interdigital electrodes. The interdigital electrodes each include
corresponding first base layers containing Ta and Cu layers or Cu—M alloy
layers each disposed on the corresponding first base layers, wherein M represents
one or more elements selected from the group consisting of Ag, Sn, and C.