Patent ID: 7332986

Claim:
A surface acoustic wave apparatus comprising: a filter device including an IDT electrode and an electrode pad which are formed on one principal face of a piezoelectric substrate; and a circuit board for mounting the face of the piezoelectric substrate on which the IDT electrode and the electrode pad are formed so as to be opposed to each other; a circular electrode surrounding the filter device formed on the face of the piezoelectric substrate on which the IDT electrode and the electrode pad are formed; a sealing circular conductor connected to the circular electrode formed on a face of the circuit board on which the piezoelectric substrate is mounted; a radiating conductor provided on a face on the opposite side of the face of the circuit board on which the piezoelectric substrate is mounted, or an inside layer of the circuit board; and a via conductor which is connected to the sealing circular conductor and passes through the circuit board down to the radiating conductor, wherein a top portion of the via conductor exists, at a top view, within the piezoelectric substrate, and a bottom portion of the via conductor exists, at a top view, within the radiating conductor.