Patent ID: 10177739

Abstract:
An elastic wave device includes an IDT electrode disposed on a LiNbO3 substrate and an aluminum nitride film or a silicon nitride film is stacked to cover the IDT electrode and utilizes a leaky elastic wave. The IDT electrode includes a metal selected from a group consisting of Cu, Al, Au, Pt, and Ni. Euler angles of the LiNbO3 are (0°±5°, θ, 0°±5°), and when X denotes a wavelength-normalized thickness of the IDT electrode and Y denotes θ of the Euler angles, Y is set in a specific range depending on the range of the wavelength-normalized thickness of the IDT electrode, the range of the wavelength-normalized thickness of the aluminum nitride film or the silicon nitride film, and the kind of metal of which the IDT electrode is composed.