US 11,955,283 B2
Dielectric ceramic composition and electronic device
Taku Murakami, Tokyo (JP); Nobuto Morigasaki, Tokyo (JP); Dan Sakurai, Tokyo (JP); Takuma Ariizumi, Tokyo (JP); and Toshihiko Kaneko, Tokyo (JP)
Assigned to TDK CORPORATION, Tokyo (JP)
Filed by TDK CORPORATION, Tokyo (JP)
Filed on Mar. 8, 2021, as Appl. No. 17/195,366.
Claims priority of application No. 2020-056534 (JP), filed on Mar. 26, 2020.
Prior Publication US 2021/0304966 A1, Sep. 30, 2021
Int. Cl. H01G 4/12 (2006.01); C04B 35/468 (2006.01); H01G 4/30 (2006.01)
CPC H01G 4/1227 (2013.01) [C04B 35/4682 (2013.01); H01G 4/30 (2013.01); C04B 2235/3206 (2013.01); C04B 2235/3224 (2013.01); C04B 2235/3236 (2013.01); C04B 2235/3239 (2013.01); C04B 2235/3262 (2013.01); C04B 2235/3418 (2013.01); C04B 2235/442 (2013.01)] 3 Claims
OG exemplary drawing
 
1. An electronic device comprising a dielectric layer and a pair of internal electrode layers sandwiching the dielectric layer, wherein
the dielectric layer including a dielectric ceramic composition,
the dielectric ceramic composition comprising a barium titanate, an oxide of an R element, an oxide of an M element, and an oxide containing Si,
the R element is one or more elements selected from Eu, Gd, Tb, Dy, Y, Ho, and Yb,
the M element is one or more elements selected from Mg, Ca, Mn, V, and Cr,
a mole ratio of an amount of the oxide of the R element in terms of R2O3 to an amount of the oxide containing Si in terms of SiO2 is 0.8:1 to 2.2:1,
a mole ratio of an amount of the oxide of the M element in terms of MO to the amount of the oxide containing Si in terms of SiO2 is 0.2:1 to 1.8:1,
50% or more of the number of dielectric particles constituting the dielectric ceramic composition are core-shell dielectric particles having a core-shell structure,
at least one of the R element, the M element, and the oxide containing Si is solid-soluted into the barium titanate in shell portions of the core-shell dielectric particles,
core portions of the core-shell dielectric particles are substantially made of the barium titanate,
at least a part of the dielectric particles are complete-solid-solution dielectric particles, and
a ratio (LB/LA) of LB to LA is 0.2 or more and 0.9 or less, where LA is a length of a line segment perpendicular to the internal electrode layers and extending from a boundary between the dielectric layer and either one of the internal electrode layers and a boundary between the dielectric layer and the other one of the internal electrode layers, and LB is a total length of the shell portions and the complete-solid-solution dielectric particles on the line segment.