Ceramic material and capacitor comprising the ceramic material

Patent metadata

Field	Value
Publication number	US-9293256-B2
Application number	US-201314391323-A
Country	US
Kind code	B2
Filing date	Feb 18, 2013
Priority date	Apr 10, 2012
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A ceramic material for capacitors uses multilayer technology of the general formula: Pb 1−1.5a−0.5b+1.5d+e+0.5f) A a B b (Zr 1−x Ti x ) (1−c−d−e−f) Li d C e Fe f Si c O 3 +y.PBO wherein A is selected from the group consisting of La, Nd, Y, Eu, Gd, Tb, Dy, Ho, Er and Yb; B is selected from the group consisting of Na, K and Ag; C is selected from the group consisting of Ni, Cu, Co and Mn; and 0<a<0.12; 0.05≦x≦0.3; 0<b<0.12; 0≦c≦0.12; 0<d<0.12; 0≦e≦0.12; 0≦f≦0.12; 0≦y≦1, and wherein b+d+e+f>0.

First claim

The invention claimed is:

1. A ceramic material for capacitors using multilayer technology of formula (I):
Pb (1−1.5a−0.5b+1.5d+e+0.5f) A a B b (Zr 1−x Ti x ) (1−c−d−e−f) Li d C e Fe f Si c O 3 +y .PBO  (I)

wherein
A is selected from the group consisting of La, Nd, Y, Eu, Gd, Tb, Dy, Ho, Er and Yb;
B is selected from the group consisting of Na, K and Ag;
C is selected from the group consisting of Ni, Cu, Co and Mn; and
0<a<0.12
0.1≦x<0.2
0.001<b<0.12
0≦c<0.12
0≦d<0.12
0≦e<0.12
0≦f<0.12
0≦y<1,

wherein
b+d+e+f>0.

2. The ceramic material according to claim 1 , wherein d=e=f=0.

3. The ceramic material according to claim 1 , wherein 0.001<e<0.12; and d=f=0.

4. The ceramic material according to claim 1 , wherein B is Na.

5. The ceramic material according to claim 1 , wherein the relative permittivity at an electric field strength of 1 kV/mm is at least 60% of the relative permittivity at an electric field strength of 0 kV/mm.

6. The ceramic material according to claim 1 , wherein the relative permittivity at an electric field strength of 2 to 5 kV/mm is at least 60% of the relative permittivity at an electric field strength of 0 kV/mm.

7. The ceramic material according to claim 1 , wherein the ceramic material has a relative permittivity of at least 500 at an electric field strength of 1 kV/mm.

8. The ceramic material according to claim 1 , wherein the ceramic material has a relative permittivity of at least 500 at an electric field strength of 2 to 5 kV/mm.

9. The ceramic material according to claim 1 , wherein the ceramic material is an antiferroelectric dielectric.

10. A capacitor comprising:
at least one ceramic layer composed of the ceramic material according to claim 1 ; and
a conductive electrode formed on the at least one ceramic layer.

11. The capacitor according to claim 10 , wherein the conductive electrode is arranged between adjacent ceramic layers.

12. The capacitor according to claim 10 , wherein the conductive electrode comprises a base metal comprising Ag or Cu.

13. The capacitor according to claim 10 , wherein the current-carrying capacity at 100° C. is at least 1 A/μF.

14. The capacitor according to claim 10 , wherein the current-carrying capacity is at least 1 A/μF in the range of −40° C. to 150° C.

15. The capacitor according to claim 11 , wherein the conductive electrode comprises a base metal comprising Ag or Cu.

16. The capacitor according to claim 11 , wherein the current-carrying capacity at 100° C. is at least 1 A/μF.

17. The capacitor according to claim 12 , wherein the current-carrying capacity at 100° C. is at least 1 A/μF.

Assignees

• Epcos Ag

Inventors

• Engel Günter
• Schossmann Michael
• Koini Markus
• Testino Andrea
• Hoffmann Christian

Classifications

• C04B2235/3418

  Silicon oxide, silicic acids or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint · CPC title

• C04B2235/449

  Organic acids, e.g. EDTA, citrate, acetate, oxalate · CPC title

• H01G4/1245 Primary

  containing also titanates · CPC title

• C04B35/493 Primary

  containing also other lead compounds · CPC title

• C04B2235/3201

  Alkali metal oxides or oxide-forming salts thereof · CPC title