Patent ID: 7893597

Claim:
A surface acoustic wave element comprising: a piezoelectric substrate; and an IDT electrode formed on a main surface of the piezoelectric substrate and having an electrode finger; wherein the electrode finger is formed by laminating a plurality of conductor layers including a first conductor layer and a second conductor layer formed of a material different from a material forming the first conductor layer, the first conductor layer has a trapezoidal shape that widens nearer to the piezoelectric substrate in a cross section, through a plane perpendicular to the longitudinal direction of the electrode finger, the second conductor layer has a trapezoidal shape that widens nearer to the piezoelectric substrate in a cross section through a plane perpendicular to the longitudinal direction of the electrode finger, the second conductor layer is formed of a material having a lower coefficient of thermal expansion than the material forming the first conductor layer, and the angle formed between the side surface of the first conductor layer and the main surface of the piezoelectric substrate is formed smaller than the angle formed between the side surface of the second conductor layer and the main surface of the piezoelectric substrate.