US 12,176,152 B2
Ceramic electronic device and manufacturing method of the same
Kyosuke Shimazaki, Tokyo (JP); Takashi Asai, Tokyo (JP); Takayuki Hattori, Tokyo (JP); Keisuke Ishii, Tokyo (JP); Shin Nishiura, Tokyo (JP); Yoshimasa Kitamura, Tokyo (JP); and Hirotaka Ohno, Tokyo (JP)
Assigned to TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed by TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed on Jun. 8, 2022, as Appl. No. 17/835,424.
Claims priority of application No. JP2021-109227 (JP), filed on Jun. 30, 2021.
Prior Publication US 2023/0005669 A1, Jan. 5, 2023
Int. Cl. H01G 4/30 (2006.01); H01G 4/012 (2006.01); H01G 4/12 (2006.01)
CPC H01G 4/30 (2013.01) [H01G 4/012 (2013.01); H01G 4/12 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A ceramic electronic device comprising:
a multilayer structure having a structure in which each of a plurality of dielectric layers of which a main component is ceramic and each of a plurality of internal electrode layers are alternately stacked and having a substantially rectangular parallelepiped shape, the plurality of internal electrode layers being alternately exposed to each of two end faces opposite to each other of the rectangular parallelepiped shape;
a first cover layer that is provided on a first end of the multilayer structure in a stacking direction, a main component of the first cover layer being ceramic; and
a second cover layer that is provided on a second end of the multilayer structure in the stacking direction, a main component of the second cover layer being ceramic, a porosity of the second cover layer being higher than that of the first cover layer,
wherein Q=(A+B)/2C×100(%) is 0.5% or more and 1.6% or less, when, at an interface between the second cover layer and an uppermost one of the internal electrode layers in a cross section vertical to a direction in which the two end faces are opposite to each other, two heights of curvature portions of both ends of the interface in the stacking direction are respectively a height A and a height B from a height C, wherein the height Cis a shortest height in the stacking direction from the first cover layer to the second cover layer, and
wherein, in the cross section, at both ends in a direction vertical to the stacking direction, an amount by which the interface between the second cover layer and the uppermost one of the internal electrode layers curves upward in the stacking direction is larger than an amount by which the interface between the first cover layer and the lowermost one of the internal electrode layers curves downward in the stacking direction, and
wherein the shortest height of the height C in the stacking direction is located at a center or around the center in the direction vertical to the stacking direction in the cross section.