Patent ID: 7208860

Claim:
A surface acoustic wave device comprising: a 25° to 55° rotation-Y plate LiTaO 3 substrate having Euler angles of (0°, 115° to 145°, 0°); at least one IDT disposed on the LiTaO 3 substrate and made of a metal having a density higher than that of Al; and an SiO 2 film arranged on the LiTaO 3 substrate so as to cover the at least one IDT; wherein the at least one IDT primarily includes at least one metal selected from the group consisting of Au, Pt, W, Ta, Ag, Mo, Cu, Ni, Co, Cr, Fe, Mn, Zn, and Ti; and the SiO 2 film has a thickness normalized by the wavelength of the surface acoustic wave in the range of about 0.03 to about 0.45.