Tdk Corporation

Akiyasu Iioka

Kazuhiro Yoshikawa

Hitoshi Saita

Tatsuo Namikawa

Yuuki Aburakawa

Kenichi Yoshida

Atsuo Matsutani

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. An inner wall surface of the through hole has a first tapered surface and a second tapered surface surrounded by the first tapered surface. The first and second tapered surfaces are not covered with the upper electrode layer and have respective first and second taper angles with respect to a surface of the lower electrode layer. The second taper angle is smaller than the first taper angle.

Thin film capacitor having a dielectric layer having a through hole whose inner surface has first and second tapered surfaces, circuit board incorporating the same, and thin film capacitor manufacturing method

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

Disclosed herein is a thin film capacitor that includes a lower electrode layer, an upper electrode layer, and a dielectric layer positioned between the lower electrode layer and the upper electrode layer. The upper electrode layer has a first capacitive electrode part opposed to the lower electrode layer through the dielectric layer without being connected to the lower electrode layer and a fiducial mark part penetrating the dielectric layer to be connected to the lower electrode layer.

Growing community of inventors

Tokyo, Japan

Akiyasu Iioka