公开(公告)号：US20180013056A1

公开(公告)日：2018-01-11

申请号：US15640747

申请日：2017-07-03

Applicant: TDK CORPORATION

Inventor： Yoshiki OHTA ,  Satoshi SASAKI ,  Yoshiaki OHTA ,  Takahiro KEZUKA ,  Katsuya INABA ,  Rin SATO ,  Kazushi TACHIMOTO ,  Masayoshi INOUE ,  Yuzo KOMATSU

IPC: H01L41/083

CPC classification number: H01L41/0838 ,  H01L41/0471 ,  H01L41/0472

Abstract: In a piezoelectric element, internal stress generated in an inactive portion at the time of sintering when a piezoelectric element is fabricated or stress applied from the outside to the inactive portion is absorbed by a recess of a lower surface of a first through hole conductor and a recess of an upper surface of a second through hole conductor. Accordingly, for example, deformation, rupture, or the like of the through hole conductor is prevented, and conduction failure or disconnection of an electrode layer or a through hole conductor is prevented. Further, in the inactive portion, since a protrusion of the piezoelectric layer enters the recess of the through hole conductor, a holding force of the piezoelectric layer with respect to the through hole conductor increases, and deformation of the through hole conductor is prevented or obstructed.