An acoustic wave device includes: a piezoelectric substrate of which four sides of an upper surface are approximate cleavage directions; and an electrode that is formed on the upper surface of the piezoelectric substrate, and excites an acoustic wave propagating in a direction different from the approximate cleavage directions.

An apparatus is disclosed for a double-mode surface-acoustic-wave (SAW) filter having a modulated interdigital transducer. In example aspects, the apparatus includes a double-mode surface-acoustic-wave filter that has at least one interdigital transducer. The interdigital transducer includes a first busbar, a second busbar, and multiple fingers extending from the first busbar toward the second busbar. The multiple fingers include a first set of fingers having a first spatial property. The multiple fingers also include a second set of fingers having a second spatial property different from the first spatial property. The second spatial property includes at least two fingers of the second set of fingers being positioned adjacent to each other.