JP2015056712A5 - - Google Patents

Claims (16)

A piezoelectric substrate having an upper surface ;
An IDT electrode disposed above an upper surface of the piezoelectric substrate, the IDT electrode including a plurality of electrode fingers configured to excite a main acoustic wave;
Wherein arranged above the upper surface of the piezoelectric substrate has covering the plurality of electrode fingers, the first dielectric film made of oxides in contact with the upper surface of the piezoelectric substrate at a position between the adjacent electrode fingers of said plurality of electrode fingers When,
The upper surface of the plurality of electrode fingers, and the non-oxide made of a second dielectric layer disposed between each of the plurality of electrode fingers and the first dielectric layer
An elastic wave device including: 2. The acoustic wave device according to claim 1, wherein the first dielectric film has a frequency temperature coefficient opposite in sign to the frequency temperature coefficient of the piezoelectric substrate. The first dielectric film, the elastic wave element according to claim 1, Ru made of silicon oxide. It said second dielectric film, an elastic wave element according to claim 1, Ru made from one of the nitrides and carbides. Said second dielectric film, an elastic wave element according to claim 4 in which Ru is made of silicon nitride. 2. The acoustic wave device according to claim 1, wherein the main acoustic wave is a Rayleigh wave. The acoustic wave device according to claim 1, wherein the second dielectric film is in contact with side surfaces of the plurality of electrode fingers. Wherein the plurality of film thickness of portions of said second dielectric film on the upper surface of the electrode fingers, a plurality of portions of the elasticity of the thick claim 7 than the thickness of the second dielectric layer you contact with the lateral side of the plurality of electrode fingers Wave element. The acoustic wave element according to claim 7, wherein the second dielectric film covers a part of each side surface of the plurality of electrode fingers from above the plurality of electrode fingers but does not reach the upper surface of the piezoelectric substrate. A third dielectric film disposed between the piezoelectric substrate and each of the plurality of electrode fingers;
The elastic wave device according to claim 1, wherein the velocity of the transverse wave propagating through the third dielectric film is faster than the velocity of the main elastic wave propagating through the piezoelectric substrate. The elastic wave device according to claim 1, wherein the velocity of the transverse wave propagating through the second dielectric film is faster than the velocity of the transverse wave propagating through the first dielectric film. A third dielectric film disposed between the piezoelectric substrate and each of the plurality of electrode fingers;
The elastic wave device according to claim 1, wherein a dielectric constant of the third dielectric film is smaller than a dielectric constant of the piezoelectric substrate. Electronic equipment,
An acoustic wave device according to claim 1 ;
And an electronic device including a reproducing device connected to the acoustic wave element. A piezoelectric substrate having an upper surface;
An IDT electrode formed above an upper surface of the piezoelectric substrate, the IDT electrode including a plurality of electrode fingers configured to excite a main acoustic wave;
A first dielectric film made of oxide that is disposed above the upper surface of the piezoelectric substrate, covers the plurality of electrode fingers, and contacts the upper surface of the piezoelectric substrate at a position between adjacent electrode fingers of the plurality of electrode fingers; ,
A non-oxide second dielectric film disposed on an upper surface of the plurality of electrode fingers and between the first dielectric film and each of the plurality of electrode fingers;
A third dielectric film formed between the piezoelectric substrate and each of the plurality of electrode fingers;
An elastic wave device including: The third dielectric film is made of a medium;
15. The acoustic wave device according to claim 14, wherein the medium allows a velocity of a transverse wave propagating through the medium to be higher than a velocity of the main elastic wave propagating through the piezoelectric substrate. An electronic device comprising the acoustic wave device according to claim 14.