Patent ID: 10270421

Abstract:
An elastic wave device includes a piezoelectric substrate, first to third IDT electrodes provided on the piezoelectric substrate, a dielectric film provided on the piezoelectric substrate and covering the first to third IDT electrodes, the thickness of the dielectric film in a first region in which the dielectric film covers the first IDT electrodes is different from the thickness of the dielectric film in a second region in which the dielectric film covers the second IDT electrodes and the thickness of the dielectric film in a third region in which the dielectric film covers the third IDT electrodes. The density equivalent thickness of each of the first IDT electrodes and the second IDT electrodes are equal to each other, and the density equivalent thickness of each of the third IDT electrodes is different from the density equivalent thickness of each of the first IDT electrodes and the second IDT electrodes.