SURFACE ACOUSTIC WAVE DEVICE AND MANUFACTURING METHOD OF SAME

摘要

Disclosed is a surface acoustic wave device upon which an insulating film is formed so as to cover an IDT electrode upon a piezoelectric substrate, wherein the frequency characteristics of the surface acoustic wave device, such as resonance characteristics and filter characteristics, are superior. A surface acoustic wave device (1) is provided with a piezoelectric substrate (10), an IDT electrode (11), an insulating film (16) formed so as to cover the IDT electrode (11) upon the piezoelectric substrate (10), and a frequency adjustment film (17) formed upon the insulating film (16). Upon the surface (16a) of the insulating film (16), a plurality of convex portions (16a1) shaped so as to correspond to the shapes of a plurality of electrode fingers (12a and 13a) are formed. The center position of the convex portions (16a1) formed upon the surface (16a) of the insulating film (16) in a surface acoustic wave propagation direction (D), and the center position of the electrode fingers (12a and 13a) corresponding to the convex portions (16a1) in the surface acoustic wave propagation direction (D), differ in the surface acoustic wave propagation direction (D).