Patent ID: 6710509
Filing Date: 2004-03-23
Classification: H03H

Abstract:
A surface acoustic wave device comprising:a quartz substrate; a piezoelectric thin film disposed on the quartz substrate and having a positive temperature coefficient of delay; and an interdigital electrode disposed in contact with the piezoelectric thin film; wherein the quartz substrate has an angle &phgr; at the Euler angle (0, &phgr;, &thgr;) which is selected such that the quartz substrate has a negative temperature coefficient of delay at a predetermined propagation direction &thgr;, and the piezoelectric thin film has a thickness H which is selected such that a fundamental mode of a leaky surface acoustic wave is excited on the quartz substrate and the surface acoustic wave device operates using the fundamental mode of the leaky surface acoustic wave; and the propagation direction &thgr; is in a range of about 85Â° to about 95Â°.