Multi-layer ceramic capacitor

Patent metadata

Field	Value
Publication number	US-9287046-B2
Application number	US-201214389287-A
Country	US
Kind code	B2
Filing date	Nov 13, 2012
Priority date	Mar 30, 2012
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A multi-layer ceramic capacitor has a structure where its dielectric layers are constituted by a sintered compact that contains a mol of ReO 3/2 , b mol of SiO 2 , c mol of MO x , d mol of ZrO 2 , and e mol of MgO (where Re is a rare earth element, M is a metal element (except for Ba, Ti, Re, Si, Zr, Mg, and rare earth elements), and x is a valance) per 100 mol of BaTiO 3 , and a, b, c, d, and e mentioned above which indicate the mol numbers of respective constituents per 100 mol of BaTiO 3 are 0.1≦a≦1.0, 0.1≦b≦1.5, 0.1≦c≦0.4, 0≦d≦1.0, and 0≦e≦0.03, respectively.

First claim

The invention claimed is:

1. A multi-layer ceramic capacitor that contains a laminate constituted by dielectric layers and internal electrode layers alternately layered with one another, as well as cover layers formed as outermost layers at a top and bottom of the laminate in a layering direction, wherein:
the dielectric layers are constituted by a sintered compact that contains a mol of ReO 3/2 , b mol of SiO 2 , c mol of MO x , d mol of ZrO 2 , and e mol of MgO (where Re is a rare earth element, M is a metal element (except for Ba, Ti, Si, Zr, Mg and rare earth elements), and x is a valance) per 100 mol of BaTiO 3 ; and
a, b, c, d, and e mentioned above which indicate mol numbers of respective constituents per 100 mol of BaTiO 3 are as follows:
0.1≦a≦1.0,
0.1≦b≦1.5,
0.1≦c≦0.4,
0≦d≦1.0, and
0≦e≦0.03.

2. A multi-layer ceramic capacitor according to claim 1 , wherein the cover layers contain 2.0 mol or less of Mg per 100 mol of BaTiO 3 .

3. A multi-layer ceramic capacitor according to claim 1 , wherein Re as mentioned above is at least one rare earth element selected from the group consisting of Y, Eu, Gd, Dy, Ho, Er and Yb.

4. A multi-layer ceramic capacitor according to claim 3 , wherein Re as mentioned above is at least one rare earth element selected from the group consisting of Y, Ho and Gd.

5. A multi-layer ceramic capacitor according to claim 1 , wherein aforesaid M is a metal element selected from Mn and/or V.

6. A multi-layer ceramic capacitor according to claim 1 , wherein a value of a specific dielectric constant per an average grain size of dielectric grains constituting the dielectric layers is 15 nm −1 or more.

7. A multi-layer ceramic capacitor according to claim 1 , wherein an average grain size of dielectric grains constituting the dielectric layers is 500 nm or less.

8. A multi-layer ceramic capacitor according to claim 1 , wherein a mol number e of MgO in the dielectric layers is in a range of 0.01≦e≦0.03.

9. A multi-layer ceramic capacitor according to claim 2 , wherein Re as mentioned above is at least one rare earth element selected from the group consisting of Y, Eu, Gd, Dy, Ho, Er and Yb.

10. A multi-layer ceramic capacitor according to claim 9 , wherein Re as mentioned above is at least one rare earth element selected from the group consisting of Y, Ho and Gd.

11. A multi-layer ceramic capacitor claim 2 , wherein aforesaid M is a metal element selected from Mn and/or V.

12. A multi-layer ceramic capacitor claim 3 , wherein aforesaid M is a metal element selected from Mn and/or V.

13. A multi-layer ceramic capacitor according to claim 2 , wherein a value of a specific dielectric constant per an average grain size of dielectric grains constituting the dielectric layers is 15 nm −1 or more.

14. A multi-layer ceramic capacitor according to claim 3 , wherein a value of a specific dielectric constant per an average grain size of dielectric grains constituting the dielectric layers is 15 nm − or more.

15. A multi-layer ceramic capacitor according to claim 2 , wherein an average grain size of dielectric grains constituting the dielectric layers is 500 nm or less.

16. A multi-layer ceramic capacitor according to claim 3 , wherein an average grain size of dielectric grains constituting the dielectric layers is 500 nm or less.

17. A multi-layer ceramic capacitor according to claim 2 , wherein a mol number e of MgO in the dielectric layers is in a range of 0.01≦e≦0.03.

18. A multi-layer ceramic capacitor according to claim 3 , wherein a mol number e of MgO in the dielectric layers is in a range of 0.01≦e≦0.03.

Assignees

• Taiyo Yuden Kk

Inventors

• Morita Koichiro
• Shimura Tetsuo
• Nagaoka Kunihiko

Classifications

• C04B2235/6025

  Tape casting, e.g. with a doctor blade · CPC title

• H01G4/224

  Housing; Encapsulation · CPC title

• H01G4/20 Primary

  using combinations of dielectrics from more than one of groups H01G4/02 - H01G4/06 (H01G4/12 takes precedence) · CPC title

• C04B2235/5445

  submicron sized, i.e. from 0,1 to 1 micron · CPC title

• C04B2235/3206

  Magnesium oxides or oxide-forming salts thereof · CPC title