Granted Patent B2

US 7,339,780 · App. 11/201,278 · Granted Mar 4, 2008

Abstract

Claims (77)

1. A capacitor comprising a copper termination, said copper termination made by firing a lead-free and cadmium-free ink including a glass component, said glass component comprising:

a. ZnO, provided the amount does not exceed 65 mole %;

b. B 2 O 3 , provided the amount does not exceed 61mole %; and,

c. SiO 2 , provided the amount does not exceed 63 mole %;

wherein the molar ratio of B 2 O 3 to SiO 2 is from about 0.05 to about 3.

2. The capacitor of claim 1 wherein the glass component further comprises:

a. Al 2 O 3 , provided the amount does not exceed 17 mole %; and

b. BaO+CaO, provided the amount does not exceed 40 mole %;

wherein the glass component excludes alkali oxides.

3. The capacitor of claim 2 further comprising at least one ingredient selected from the group consisting of 2-25 mol % Li 2 O+Na 2 O+K 2 O+Rb 2 O+Cs 2 O+Fr 2 O, and 0.1-15 mol % TiO 2 +ZrO 2 .

4. The capacitor of claim 1 wherein the molar ratio of B 2 O 3 to SiO 2 is from about 0.05 to about 3 and wherein the glass component comprises:

a. about 10 to about 60 mole % ZnO;

b. about 1 to about 40 mole % B 2 O 3 ;

c. about 1 to about 55 mole % SiO 2 ; and further comprises

d. about 0.1 to about 17 mole % Al 2 O 3 ; and,

e. BaO+CaO, provided the combined amount of BaO+CaO does not exceed about 30 mole %.

5. The capacitor of claim 4 further comprising at least one ingredient selected from the group consisting of:

a. about 0.1 to about 20 mol % Co 3 O 4 ;

b. about 0.1 to about 20 mol % MnO 2 ; and,

c. about 0.1 to about 20 mol % CuO.

6. The capacitor of claim 4 further comprising about 5 to about 18 mole % Li 2 O +Na 2 O+K 2 O+Rb 2 O+Cs 2 O+Fr 2 O.

7. The capacitor of claim 1 wherein the glass component comprises:

a. about 25 to about 55 mole % ZnO;

b. about 15 to about 25 mole % B 2 O 3 ; and,

c. about 10 to about 30 mole % SiO 2 .

8. The capacitor of claim 7 wherein the glass component further comprises:

a. about 1 to about 7 mole % Al 2 O 3 ;

b. about 5 to about 15 mole % BaO+CaO; and,

c. wherein the glass component excludes alkali oxides.

9. The capacitor of claim 8 , wherein the glass component further comprises at least one ingredient selected from the group consisting of

a. about 5 to about 10 mole % TiO 2 +ZrO 2 ;

b. about 1 to about 10 mole % MgO; and,

c. about 1 to about 20 mole % F.

10. The capacitor of claim 9 wherein the glass component further comprises about 5 to about 15 mole % Li 2 O+Na 2 O+K 2 O+Rb 2 O+Cs 2 O+Fr 2 O.

11. The capacitor of claim 1 , wherein the glass component comprises:

a. about 20 to about 30 mole % ZnO;

b. about 15 to about 25 mole % B 2 O 3 ; and

c. about 35 to about 50 mole % SiO 2 .

12. The capacitor of claim 11 , wherein the glass component further comprises:

a. about 0.1 to about 5 mole % Al 2 O 3 ;

b. about 1 to about 13 mole % Li 2 O+Na 2 O+K 2 O+Rb 2 O+Cs 2 O+Fr 2 O; and

c. about 5 to about 15 mole % TiO 2 +ZrO 2 .

13. The capacitor of claim 12 , wherein the glass component further comprises at least one ingredient selected from the group consisting of

a. about 1 to about 20 mole % F, and

b. about 0.1 to about 5 mole % of at least one ingredient selected from the group consisting of In 2 O 3 , SnO, CuO, NiO, and MnO.

14. The capacitor of claim 1 , wherein the glass component comprises:

a. about 15 to about 25 mole % ZnO;

b. about 15 to about 20 mole % B 2 O 3 ; and,

c. about 33 to about 49 mole % SiO 2 .

15. The capacitor of claim 14 , wherein the glass component further comprises:

a. about 0.1 to about 5 mole % Al 2 O 3 and

b. about 5 to about 10 mole % Li 2 O+Na 2 O+K 2 O+Rb 2 O+Cs 2 O+Fr 2 O.

16. The capacitor of claim 15 , wherein the glass component further comprises:

a. about 5 to about 15 mole % TiO 2 ZrO 2 and

b. about 1 to about 20 mole % F.

17. A capacitor comprising a copper termination, said copper termination made by firing a lead-free and cadmium-free ink including a glass component, said glass component comprising a first glass and a second glass frit, wherein the first frit comprises:

a. about 5 to about 20 mole % B 2 O 3 and about 70 to about 90 mole % SiO 2 , and the second frit comprises

b. about 25 to about 55 mole % ZnO, and about 15 to about 25 mole % B 2 O 3 , and about 10 to about 30 mole % SiO 2 ,

wherein the weight ratio of the first frit to the second frit is from about 1:20 to about 20:1, and wherein the overall molar ratio of B 2 O 3 to SiO 2 is from about 0.05 to about 1.

18. A lead-free and cadmium-free ink for forming a conductive copper pathway, said ink comprising a metal component and about 1 to about 22 percent by weight of glass component, said glass component comprising:

a. ZnO, provided the amount does not exceed 65 mole %

b. B 2 O 3 , provided the amount does not exceed 61 mole %;

c. SiO 2 , provided the amount does not exceed 63 mole %; and,

d. wherein the molar ratio of B 2 O 3 to SiO 2 is from about 0.05 to about 3.

19. The ink of claim 18 , wherein the glass component further comprises at least one ingredient selected from the group consisting of:

a. about 0.1 to about 20 mole % MgO;

b. about 0.1 to about 40 mole % BaO+CaO; and,

c. about 0.1 to about 17 mole % Al 2 O 3 .

20. A process for making a multilayer ceramic chip capacitor having conductive end terminations comprising:

a. forming a green chip by stacking alternating layers of a dielectric material and a conductive electrode material,

b. firing the green chip to form a multilayer ceramic chip capacitor body,

c. applying a conductive lead-free and cadmium-free ink to the ceramic chip capacitor body, and said ink comprising a glass component, said glass component comprising:

i. ZnO, provided the amount does not exceed 65 mole %;

ii. B 2 O 3 , provided the amount does not exceed 61mole %; and,

iii. SiO 2 , provided the amount does not exceed 63 mole %;

iv. wherein the molar ratio of B 2 O 3 to SiO 2 is from about 0.05 to about 3; and,

v. post-firing the chip and forming the conductive end terminations.

Assignments (14)