Patent ID: 8598968
Filing Date: 2013-12-03
Classification: H03H

Abstract:
1. An elastic wave device comprising: a piezoelectric substrate; an IDT electrode disposed on the piezoelectric substrate; a first dielectric layer disposed on the piezoelectric substrate, the first dielectric layer covering the IDT electrode and being made of a medium with a frequency-temperature characteristic opposite to that of the piezoelectric substrate; and a second dielectric layer disposed on the first dielectric layer, the second dielectric layer being made of a medium that propagates a transverse wave faster than a speed of a transverse wave propagating on the first dielectric layer; wherein the first dielectric layer has a convex portion on a top face of the first dielectric layer, the convex portion being provided over the IDT electrode; and wherein a relation of one of is satisfied, where t t h is a film thickness of the IDT electrode, and λ is a wavelength of a major wave excited by the IDT electrode.