Patent ID: 8179023

Claim:
A package-type piezoelectric resonator in which a vibrating portion is provided in a space airtightly sealed by a cover and a base, the piezoelectric resonator comprising: a piezoelectric substrate in which the vibrating portion and a frame portion surrounding the vibrating portion via a gap are integrally formed via a support portion; one excitation electrode and another excitation electrode formed on one surface side and another surface side of the vibrating portion respectively; one lead electrode connected to said one excitation electrode and led out from one edge side of the vibrating portion to the frame portion on the other surface side of said piezoelectric substrate via the support portion; another lead electrode connected to said other excitation electrode and led out to a position that is separated in a crosswise direction from said one lead electrode on the frame portion on the other surface side of said piezoelectric substrate via the support portion; the cover having a recessed portion housing the vibrating portion and the support portion; and the base having a recessed portion housing the vibrating portion and the support portion, wherein: said base has: stepped surfaces which are formed at portions respectively facing said one and other lead electrodes on an inner circumferential edge side on a top face of an annular protruding wall surrounding the recessed portion of said base so as to be lower than another portion of the top face of said annular protruding wall by a dimension that is slightly less than film thickness of said lead electrodes; one through hole and another through hole formed at positions, in the stepped surfaces, not communicating with a space in the recessed portion of said base and being open to the piezoelectric substrate at an outer surface of said base at said stepped surfaces; a top face of an annular protruding wall of said cover and a top face of an annular protruding wall of the base are joined with the frame portion of said piezoelectric substrate trapped therebetween; one lead electrode formed onto an other side of the frame portion of said piezoelectric substrate is positioned extending across an opening on the stepped surface side of said one through hole so as to close said opening, and another lead electrode formed onto the other side of the frame portion of said piezoelectric substrate, is positioned extending across an opening on the stepped surface side of said other through hole so as to close said opening, the lead electrodes being pressed into and sunken into the stepped surface whereby an airtight seal is achieved between the through holes and the recessed portion of the base; and by forming conduction electrodes on the inner circumferential faces of the one through hole and the other through hole and on the surfaces of the lead electrodes that cover the through holes, the external electrodes and the lead electrodes are electrically connected via the conduction electrodes.