| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-reliability acoustic wave device by restraining an interdigital electrode from spread in an insulating film. <P>SOLUTION: The acoustic wave device 100 includes a piezoelectric substrate 10, an interdigital electrode 18 provided on the piezoelectric substrate 10, a first insulating film 12 provided between electrode fingers of the interdigital electrode 18, a first diffusion-preventing film 16 provided between the interdigital electrode 18 and the first insulating film 12 so as to cover the side face of the interdigital electrode 18, an insulating second diffusion-preventing film 20 provided on the interdigital electrode 18 and the first insulating film 12, and a second insulating film 22 provided on the second diffusion preventing film 20. According to the configuration, since the first diffusion-preventing film 16 is provided between the interdigital electrode 18 and the first insulating film 12, the interdigital electrode 18 is restrained from diffusing into the first insulating film 12. As a result, the reliability of the surface acoustic wave device is improved. <P>COPYRIGHT: (C)2011,JPO&INPIT |
