Surface acoustic wave devices using optimized cuts of lithium niobate (LiNbO3)

摘要

A surface acoustic wave device includes a piezoelectric substrate of a single crystal LiNbO₃ and an electrode pattern provided on a surface of the piezoelectric substrate which forms a resonator having an electrode thickness in a range of about 0.1% to about 8% of an acoustic wavelength of a surface acoustic wave excited on the surface of the substrate. The piezoelectric substrate has an orientation defined by Euler angles (&lgr;,&mgr;,&thgr;), with angle &lgr; in a range from −20° to +20°, angle &mgr; in a range from about −45° to about −10°, and angle &thgr; in a range from about (−1.16&lgr;−1.5)° to (−1.16&lgr;+1.5)°, wherein one of angle &lgr; and &thgr; is not equal to zero degrees. Such orientations simultaneously combined with an optimized propagation loss at resonant and anti-resonant frequencies provide for improved performance in RF applications.