Dielectric ceramic and multilayer ceramic capacitor

Patent metadata

Field	Value
Publication number	US-9530564-B2
Application number	US-201514869438-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Apr 8, 2013
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

A dielectric ceramic that contains Al and Si, as well as a barium titanate-based compound having a perovskite type crystal structure as a primary component. The total molar amount of Al and Si is 2 to 4 parts by mole with respect to 100 parts by mole of Ti, and the content ratio of Al with respect to the total molar amount is 0.2 or less (excluding 0) on the molar ratio basis. The dielectric ceramic may also contain at least one specific rare earth element Re, such as Gd, Tb, or Dy.

First claim

The invention claimed is:

1. A dielectric ceramic containing:
a barium titanate-based compound having a perovskite type crystal structure as a primary component;
Al;
Si;
Mg;
Mn;
V; and
Zr,
wherein a total of content molar amounts of the Al and the Si is 2 parts by mole to 4 parts by mole with respect to 100 parts by mole of Ti,
a content ratio of the Al with respect to the total of content molar amounts of the Al and the Si is 0.2 or less, excluding 0, on a molar ratio basis, and
with respect to 100 parts by mole of the Ti,
the Mg is 0.10 parts by mole to 2.0 parts by mole,
the Mn is 0.01 parts by mole to 0.30 parts by mole,
the V is 0.01 parts by mole to 0.30 parts by mole, and
the Zr is 0.20 parts by mole to 0.80 parts by mole, respectively.

2. The dielectric ceramic according to claim 1 , further containing a rare earth element Re.

3. The dielectric ceramic according to claim 2 , wherein a content molar amount of the Re is 0.95 to 2.0 parts by mole with respect to 100 parts by mole of the Ti.

4. The dielectric ceramic according to claim 2 , wherein the rare earth element Re includes at least one type selected from Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.

5. The dielectric ceramic according to claim 2 , wherein the rare earth element Re includes at least one type selected from Gd, Tb, and Dy.

6. A multilayer ceramic capacitor comprising:
a plurality of dielectric layers; and
internal electrode layers alternately laminated to the plurality of dielectric layers,
wherein the plurality of dielectric layers are each formed of the dielectric ceramic according to claim 1 .

7. The multilayer ceramic capacitor according to claim 6 , wherein the internal electrode layers each have a thickness of 0.6 μm or less.

8. The multilayer ceramic capacitor according to claim 6 , wherein the internal electrode layers each contain Ni as a primary component.

9. A multilayer ceramic capacitor comprising:
a plurality of dielectric layers; and
internal electrode layers alternately laminated to the plurality of dielectric layers,
wherein the plurality of dielectric layers are each formed of the dielectric ceramic according to claim 2 .

10. The multilayer ceramic capacitor according to claim 9 , wherein the internal electrode layers each have a thickness of 0.6 μm or less.

11. The multilayer ceramic capacitor according to claim 9 , wherein the internal electrode layers each contain Ni as a primary component.

Assignees

• Murata Manufacturing Co

Inventors

• Yao Takayuki

Classifications

• C04B35/62685

  characterised by the order of addition of constituents or additives · CPC title

• H01B3/12

  ceramics · CPC title

• C04B2235/3236

  Alkaline earth titanates · CPC title

• C04B2235/6584

  at an oxygen percentage below that of air · CPC title

• H01G4/0085

  Fried electrodes · CPC title