Granted Patent B2

US 12,288,645 · App. 18/591,981 · Granted Apr 29, 2025

Inventors: Yuji Tsushima (Takasaki, JP); Koichiro Morita (Takasaki, JP)

Assignee: TAIYO YUDEN CO., LTD.

H01G4/1227C04B35/4682C04B35/62675H01G4/008H01G4/012H01G4/30

Abstract

Claims (30)

1. A dielectric body comprising:

a plurality of crystal grains of which a main component is barium titanate; and

an additive including Zr, Eu and Mn,

wherein at least one of the plurality of crystal grains has a core-shell structure having a core and a shell, a main component of the core being barium titanate, a main component of the shell being barium titanate, a Zr concentration of the shell being higher than that of the core,

wherein a Zr/Ti atomic concentration ratio is 0.02 or more and 0.10 or less,

wherein an Eu/Ti atomic concentration ratio is 0.001 or more and 0.03 or less,

wherein a Mn/Ti atomic concentration ratio is 0.005 or more and 0.05 or less.

2. The dielectric body as claimed in claim 1 , wherein a rare earth element of the additive is only Eu.

3. A multilayer ceramic capacitor comprising:

a multilayer structure having a structure in which each of a plurality of dielectric layers and each of a plurality of internal electrode layers are alternately stacked and having a substantially rectangular parallelepiped shape,

wherein each of the plurality of internal electrode layers are alternately exposed to each of two different faces of the rectangular parallelepiped shape,

wherein a section in which internal electrode layers exposed to the two different faces face each other is a capacity section,

wherein dielectric layers in the capacity section have a plurality of crystal grains of which a main component is barium titanate and an additive including Zr, Eu and Mn,

wherein at least one of the plurality of crystal grains has a core-shell structure having a core and a shell, a main component of the core being barium titanate, a main component of the shell being barium titanate, a Zr concentration of the shell being higher than that of the core,

wherein a Zr/Ti atomic concentration ratio of the dielectric layers in the capacity section is 0.02 or more and 0.10 or less,

wherein an Eu/Ti atomic concentration ratio of the dielectric layers in the capacity section is 0.001 or more and 0.03 or less,

wherein a Mn/Ti atomic concentration ratio of the dielectric layers in the capacity section is 0.005 or more and 0.05 or less.

4. The multilayer ceramic capacitor as claimed in claim 3 , wherein X8R characteristic is satisfied.

5. A manufacturing method of a dielectric body comprising:

forming a dielectric body by firing a dielectric green sheet at a temperature elevation rate of 5000° C./h or more and 10000° C./h or less,

wherein the dielectric green sheet includes barium titanate powder and an additive including Zr, Eu and Mn,

wherein a Zr/Ti atomic concentration ratio in the dielectric green sheet is 0.02 or more and 0.10 or less,

wherein an Eu/Ti atomic concentration ratio in the dielectric green sheet is 0.001 or more and 0.03 or less,

wherein a Mn/Ti atomic concentration ratio in the dielectric green sheet is 0.005 or more and 0.05 or less.

6. A manufacturing method of a multilayer ceramic capacitor comprising:

forming a ceramic multilayer structure by stacking stack units in which metal conductive paste is printed on a dielectric green sheet including barium titanate powder and an additive including Zr, Eu and Mn; and

firing the ceramic multilayer structure at a temperature elevation rate of 5000° C./h or more and 10000° C./h or less so that dielectric layer are formed from the dielectric green sheet,

wherein a Zr/Ti atomic concentration ratio in the dielectric green sheet is 0.02 or more and 0.10 or less,

wherein an Eu/Ti atomic concentration ratio in the dielectric green sheet is 0.001 or more and 0.03 or less,

wherein a Mn/Ti atomic concentration ratio in the dielectric green sheet is 0.005 or more and 0.05 or less.

Assignments (1)

Priority Claims (1)

Continuity (2)

References Cited (20)