Multi-layered substrate for a surface-acoustic-wave device

摘要

This invention provides a multi-layered substrate for a surface-acoustic-wave device which substrate comprises a piezoelectric layer on a base, the temperature coefficient of a phase velocity of the surface-acoustic-wave in the piezoelectric layer being different from that of the base, the piezoelectric layer having a thickness less than a wavelength of the SAW. This multi-layered substrate can have a large electromechanical coupling and controlled temperature coefficient of the phase velocity.