Dielectric ceramic composition and electronic device

1. A dielectric ceramic composition comprising a plurality of dielectric particles each having a shell, wherein subcomponents are dispersed in a main component, formed around a core substantially composed of the main component, wherein

a difference of a maximum thickness t 1 and a minimum thickness t 2 (t 1 −t 2 ) of said shell in a dielectric particle having an average particle diameter is controlled to be 10 to 40% of a radius R of said dielectric particle.

2. The dielectric ceramic composition as set forth in claim 1 , wherein said main component includes barium titanate and said subcomponents include an oxide of Mg, an oxide of rare-earth element and an oxide of an alkaline earth element, wherein Mg is excluded.

3. The dielectric ceramic composition as set forth in claim 1 , wherein:

said main component includes barium titanate; and

said subcomponents includes

at least one kind selected from MgO, CaO, BaO and SrO as a first subcomponent,

a silicon oxide as a second subcomponent,

at least one kind selected from V 2 O 5 , MoO 3 and WO 3 as a third subcomponent,

an oxide of R 1 , wherein is at least one kind selected from Sc, Er, Tm, Yb and Lu, as a fourth subcomponent,

CaZrO 3 or CaO+ZrO 2 as a fifth subcomponent,

an oxide of R 2 wherein R 2 is at least one kind selected from Y, Dy, Ho, Tb, Gd and Eu, as a sixth subcomponent, and

MnO as a seventh subcomponent;

and ratios of the respective subcomponents with respect to 100 moles of said main component are

the first subcomponent: 0.1 to 3 moles,

the second subcomponent: 2 to 10 moles,

the third subcomponent: 0.01 to 0.5 mole,

the fourth subcomponent: 0.5 to 7 moles, wherein the number of moles of the fourth subcomponent is a ratio of R 1 alone,

the fifth subcomponent: 0<fifth subcomponent≦5 moles,

the sixth subcomponent: 9 moles or less, wherein the number of moles of the sixth subcomponent is a ratio of R 2 alone, and

the seventh subcomponent: 0.5 mole or less.

4. The dielectric ceramic composition as set forth in claim 1 , wherein:

said main component includes barium titanate; and

said subcomponents includes

an oxide of AE, wherein AE is at least one kind selected from Mg, Ca, Ba and Sr, as a first subcomponent,

an oxide of R, wherein R is at least one kind selected from Y, Dy, Tm, Ho and Er, as a second subcomponent,

MxSiO 3 , wherein M is at least one kind selected from Ba, Ca, Sr, Li and B; and x=1 when M=Ba, x=1 when M=Ca, X=1 when M=Sr, x=2 when M=Li and x=⅔ when M=B, as a third subcomponent,

MnO as a fourth subcomponent,

at least one kind selected from V 2 O 5 , MoO 3 and WO 3 as a fifth subcomponent, and

CaZrO 3 or CaO+ZrO 2 as a sixth subcomponent;

and ratios of the respective subcomponents with respect to 100 moles of said main component are

the first subcomponent: 0 to 0.1 mole, wherein 0 mole and 0.1 mole are excluded,

the second subcomponent: 1 to 7 moles, wherein 1 mole and 7 moles are excluded,

the third subcomponent: 2 to 10 moles,

the fourth subcomponent: 0 to 0.5 mole, wherein 0 mole is excluded,

the fifth subcomponent: 0.01 to 0.5 mole, and

the sixth subcomponent: 0 to 5 moles, wherein 0 mole and 5 moles are excluded.

5. An electronic device comprising a dielectric layer composed of a dielectric ceramic composition, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic set forth in claim 1 .

6. A multilayer ceramic capacitor comprising a capacitor element body, wherein dielectric layers composed of a dielectric ceramic composition and internal electrode layers are alternately stacked, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 1 .

7. An electronic device comprising a dielectric layer composed of a dielectric ceramic composition, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 2 .

8. An electronic device comprising a dielectric layer composed of a dielectric ceramic composition, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 3 .

9. An electronic device comprising a dielectric layer composed of a dielectric ceramic composition, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 4 .

10. A multilayer ceramic capacitor comprising a capacitor element body, wherein dielectric layers composed of a dielectric ceramic composition and internal electrode layers are alternately stacked, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 2 .

11. A multilayer ceramic capacitor comprising a capacitor element body, wherein dielectric layers composed of a dielectric ceramic composition and internal electrode layers are alternately stacked, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 3 .

12. A multilayer ceramic capacitor comprising a capacitor element body, wherein dielectric layers composed of a dielectric ceramic composition and internal electrode layers are alternately stacked, wherein:

said dielectric ceramic composition is composed of the dielectric ceramic composition as set forth in claim 4 .