Patent ID: 8564172

Claim:
An acoustic wave element comprising: a piezoelectric body having an upper surface; a first interdigital transducer (IDT) electrode provided on the upper surface of the piezoelectric body; a second IDT electrode provided on the upper surface of the piezoelectric body; and a first dielectric layer provided on the upper surface of the piezoelectric body to cover the first IDT electrode and the second IDT electrode, wherein the first dielectric layer has a first part directly above the first IDT electrode and a second part directly above the second IDT electrode, and wherein a height of an upper surface of the second part of the first dielectric layer is larger than a height of an upper surface of the first part of the first dielectric layer, wherein an upper surface of the first dielectric layer has: a first projection positioned directly above the first IDT electrode and extending along the first IDT electrode; and a second projection positioned directly above the second IDT electrode and extending along the second IDT electrode, and wherein a height of the second projection is larger than a height of the first projection.