Dielectric ceramic composition, electronic device and the production method

Abstract

A production method of a dielectric ceramic composition comprising a main component including barium titanate expressed by a composition formula of BamTiO2+m, wherein “m” satisfies 0.990

Description

BRIEF DESCRIPTION OF DRAWINGS

These and other objects and features of the present invention will become clearer from the following description of the preferred embodiments given With reference to the attached drawing, in which:

FIG. 1 is a sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention.

Claims

1. A production method of a dielectric ceramic composition for producing a dielectric ceramic composition comprising a main component including barium titanate expressed by a composition formula of BamTiO2+m, wherein “m” satisfies −0.990<m<1.010, anda fourth subcomponent including an oxide of R (note that R is at least one kind selected from Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu);wherein a material of said main component is brought to react with at least a part of a material of said fourth subcomponent in advance to obtain a post-reaction material and the post-reaction material is used for the production method.

2. The production method of a dielectric ceramic composition as set forth in claim 1, wherein a material of said main component and at least a part of a material of said fourth subcomponent are dispersed as solid solution in advance to obtain a post-reaction material and the post-reaction material is used for the production method.

3. The production method of a dielectric ceramic composition as set forth in claim 1, comprising the steps of: preparing a post-reaction material obtained by bringing a material of said main component react with a part of a material of said fourth subcomponent to be included in said dielectric ceramic composition in advance; andadding to said post-reaction material remaining material of said fourth subcomponent to be included in said dielectric ceramic composition.

4. The production method of a dielectric ceramic composition as set forth in claim 1, wherein a content of said fourth subcomponent in finally obtained said dielectric ceramic composition is 0.1 to 10 moles when calculated as a conversion of R with respect to 100 moles of said main component.

5. The production method of a dielectric ceramic composition as set forth in claim 1, wherein a content of said fourth subcomponent to be brought to react with a material of said main component in advance is 0 to 0.5 mole (note that 0 is not included) when calculated as a conversion of R with respect to 100 moles of said main component.

6. The production method of a dielectric ceramic composition as set forth in claim 1, wherein a ratio of said fourth subcomponent to be brought to react with a material of said main component in advance is 0 to 50 mole % (note that 0 and 50 are not included) when calculated as a conversion of R with respect to a total amount of 100 mole % of said fourth subcomponent to be finally included in said dielectric ceramic composition.

7. The production method of a dielectric ceramic composition as set forth in claim 1, wherein: said dielectric ceramic composition furthermore comprisesa first subcomponent including at least one kind selected from MgO, CaO, BaO and SrO,a second subcomponent including SiO2 mainly and at least one kind selected from MO (note that M is at least one kind selected from Mg, Ca, Ba and Sr), Li2O and B2O3, anda third subcomponent including at least one kind selected from V2O5, MoO3 and WO3;wherein ratios of the respective subcomponents with respect to 100 moles of said main component are the first subcomponent: 0.1 to 5 moles,the second subcomponent: 0.1 to 12 moles, andthe third subcomponent: 0 to 0.3 mole (note that 0 is not included).

8. The production method of a dielectric ceramic composition as set forth in claim 7, wherein: said dielectric ceramic composition furthermore comprises a fifth subcomponent including at least one kind selected from MnO and Cr2O3; anda ratio of the fifth subcomponent with respect to 100 moles of said main component is 0.05 to 1.0 mole.

9. The production method of a dielectric ceramic composition as set forth in claim 1, wherein a material having an average particle diameter of 0.05 to 0.5 μm is used as a material of said main component.

10. A dielectric ceramic composition produced by the method as set forth in claim 1.

11. An electronic device comprising a dielectric layer composed of the dielectric ceramic composition as set forth in claim 10.