Temperature-Compensated High-Frequency Surface Acoustic Wave Device

摘要

We report high-frequency surface acoustic wave (SAW) devices with excellent temperature stability using a layered structure consisting of single-crystal ${rm LiNbO}_{3}$ thin film on ${rm SiO}_{2}/{rm LiNbO}_{3}$ substrate. SAW devices with a wavelength of 2 $mu{rm m}$ have been fabricated and several wave modes ranging from ${sim}{1.5}$ to 2.1 GHz have been obtained. With the ${rm SiO}_{2}$ interlayer providing the temperature compensation and the top single-crystal Z-cut ${rm LiNbO}_{3}$ piezoelectric thin film for acoustic wave excitation, the fabricated SAW devices exhibit excellent temperature coefficients of frequency. Theoretical calculations are presented to elucidate temperature compensation of the proposed layered structure.