Tdk Corporation

Atsuo Matsutani

Hitoshi Saita

Kazuhiro Yoshikawa

Tatsuo Namikawa

Masahiro Oishi

Yuuki Aburakawa

Masahiro Hiraoka

Ryu Ohta

Suguru Andoh

Akiyasu Iioka

Disclosed herein a thin film capacitor that includes a lower electrode layer, an upper electrode layer, and a dielectric layer disposed between the lower electrode layer and the upper electrode layer. The dielectric layer has a through hole. The upper electrode layer has a connection part connected to the lower electrode layer through the through hole and an electrode part insulated from the connection part by a slit. A surface of the lower electrode layer that contacts the connection part through the through hole includes an annular area positioned along an inner wall surface of the through hole and a center area surrounded by the annular area. The annular area is lower in surface roughness than the center area.

Thin film capacitor, circuit board incorporating the same, and thin film capacitor manufacturing method

Provided is a thin film capacitor that includes: a first electrode layer having a principal surface in which a plurality of recesses are provided; a dielectric layer laminated on the principal surface of the first electrode layer; and a second electrode layer laminated on the dielectric layer. When a depth of the recess is defined as FL and a thickness of the dielectric layer is defined as T, H/T is 0.05 or more and 0.5 or less.

Thin film capacitor

A piezoelectric layer made of potassium sodium niobate which is a perovskite type compound represented by the formula ABO, wherein, in the Raman spectroscopy measurement of the piezoelectric layer which is performed while the piezoelectric layer is rotated in the in-plane direction, the measured intensity of the lattice vibration region of the perovskite type compound in the Raman spectrum obtained in polarized Raman spectroscopy measurement (yx) has a periodicity of approximately 90&#xb0;, wherein, the polarized Raman spectroscopy measurement (yx) is performed while the piezoelectric layer is rotated in the in-plane direction and Raman scattering light is polarized in a direction perpendicular to that of the incident light.

Piezoelectric layer, piezoelectric component, piezoelectric actuator, piezoelectric sensor, hard-disk drive and ink jet printer

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Tokyo, Japan

Atsuo Matsutani