US Patent 9748923 Elastic wave device and manufacturing method for same

An elastic wave device includes a support layer with a through-hole or a recess opened at an upper surface thereof, a piezoelectric thin film arranged on the support layer to extend above the recess or the through-hole of the support layer, and an IDT electrode defined on at least one of upper and lower surfaces of the piezoelectric thin film in a region of the piezoelectric thin film, the region extending above the recess, or the through-hole. A secondary mode of a plate wave, which contains a U1 component as a main component, is utilized. The piezoelectric thin film is made of LiTaO3, and Euler angles (φ, θ, ψ) of the LiTaO3 fall within specific ranges.