| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric filter, with which an unwanted sprious can be effectively suppressed and the reliability of an external electrode is hardly damaged even when the height is reduced. SOLUTION: An energy sealed piezoelectric filter 1 has a structure wherein first and second piezoelectric substrates 2 and 3 are adhered/laminated through an adhesive sheet 9. The elastic modulus of the adhesive sheet 9 is within the range of 0.5 MPa to 3000 MPa, at least one of recessed parts 9b-9d and 9e-9g is formed at the outer peripheral edge of the adhesive sheet 9, and external electrode materials enter the recessed part. |
