Dielectric ceramic composition and electronic component

Patent metadata

Field	Value
Publication number	US-11639313-B2
Application number	US-202117551633-A
Country	US
Kind code	B2
Filing date	Dec 15, 2021
Priority date	Dec 21, 2020
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

A dielectric ceramic composition contains dielectric particles containing a main component represented by a composition formula (Ba 1-x-y Sr x Ca y ) m (Ti 1-z Zr z )O 3 and grain boundaries present between the dielectric particles. The values of m, x, y, and z in the composition formula are all molar ratios. In the composition formula, 0.9≤m≤1.4, 0≤x<1.0, 0<y≤1.0, 0.9≤(x+y)≤1.0, and 0.9≤z≤1.0 are satisfied. The dielectric particles contain specific structural particles having a predetermined intragranular structure, and each of the specific structural particles intragranularly includes a first region and a second region having different Ca concentrations from each other. C2/C1 is less than 0.8 in which C1 is an average value of the Ca concentration in the first region and C2 is an average value of the Ca concentration in the second region.

First claim

What is claimed is:

1. A dielectric ceramic composition, comprising:
dielectric particles containing a main component represented by a composition formula (Ba 1-x-y Sr x Ca y ) m (Ti 1-z Zr z )O 3 ; and
grain boundaries present between the dielectric particles, wherein
m, x, y, and z in the composition formula are all molar ratios,
0.9≤m≤1.4, 0≤x<1.0, 0<y≤1.0, 0.9≤(x+y)≤1.0, and 0.9≤z≤1.0 are satisfied in the composition formula,
the dielectric particles contain specific structural particles having a predetermined intragranular structure, and each of the specific structural particles intragranularly includes a first region and a second region having different Ca concentrations from each other, and
C2/C1 is less than 0.8 in which C1 is an average value of the Ca concentration in the first region and C2 is an average value of the Ca concentration in the second region.

2. The dielectric ceramic composition according to claim 1 , wherein
the second region includes a particle center of the specific structural particle, and
the first region surrounds the second region.

3. The dielectric ceramic composition according to claim 1 , wherein
C2/C1 is less than 0.7.

4. The dielectric ceramic composition according to claim 1 , wherein
C2/C1 is less than 0.5.

5. The dielectric ceramic composition according to claim 1 , wherein
an area occupied by the first region is A1, an area occupied by the second region is A2, a sum of A1 and A2 is A0, and A2/A0 is greater than 0.05 and less than 0.6, in a cross section of the dielectric ceramic composition.

6. The dielectric ceramic composition according to claim 5 , wherein
A2/A0 is less than 0.4.

7. The dielectric ceramic composition according to claim 5 , wherein
A2/A0 is greater than 0.1 and less than 0.4.

8. The dielectric ceramic composition according to claim 1 , wherein
a number ratio of the specific structural particles to the dielectric particles is 50% or more.

9. The dielectric ceramic composition according to claim 1 , wherein
a number ratio of the specific structural particles to the dielectric particles is 80% or more.

10. An electronic component, comprising:
the dielectric ceramic composition according to claim 1 .

Assignees

• Tdk Corp

Inventors

• Sakurai Dan
• Ito Yasuhiro
• Morigasaki Nobuto
• Kaneko Toshihiko
• Iguchi Toshihiro

Classifications

• C04B2235/3249

  containing also titanium oxide or titanates, e.g. lead zirconate titanate (PZT) · CPC title

• C04B2235/6582

  Hydrogen containing atmosphere · CPC title

• C04B35/638

  Removal thereof · CPC title

• C04B35/6281 Primary

  Alkaline earth metal oxides · CPC title

• C04B2235/768

  Perovskite structure ABO3 · CPC title