A surface acoustic wave device includes a piezoelectric substrate and an electrode
provided on the substrate. The electrode includes a first metal layer provided
on the piezoelectric substrate and having a trapezoid shape in the cross section
and a second metal layer provided over the piezoelectric substrate at the same
position as the first metal layer over the piezoelectric substrate. By controlling
the shape of side surfaces of the electrode, the surface acoustic wave device hardly
vary in a propagation frequency.