Ceramic substrate having a sealed layer

• US 6,136,419 A
• Filed: 05/26/1999
• Issued: 10/24/2000
• Est. Priority Date: 05/26/1999
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Reddy, Srinivasa S. N., Knickerbocker, John U., Fasano, Benjamin V., Indyk, Richard F., O'Connor, Daniel P., Langenthal, Scott I., Kamath, Sundar M.
• Primary Examiner(s): LAM, CATHY FONG FONG
• Application Number:
  US09/320,532
• Time in Patent Office: 517 Days
• Field of Search: 174/250, 174/251, 174/257, 174/262, 174/263, 428/209, 428/210
• US Class Current: 428/210
• CPC Class Codes: B32B 18/00 Layered products essentially comprising ceramics, e.g. refractory products
• CPC Class Codes: C04B 2237/343 Alumina or aluminates
• CPC Class Codes: C04B 2237/345 Refractory metal oxides
• CPC Class Codes: C04B 2237/346 Titania or titanates
• CPC Class Codes: C04B 2237/348 Zirconia, hafnia, zirconates or hafnates
• CPC Class Codes: C04B 2237/407 Copper
• CPC Class Codes: C04B 2237/408 Noble metals, e.g. palladium, platina or silver
• CPC Class Codes: C04B 2237/706 of one or more of the metallic layers or articles
• CPC Class Codes: C04B 2237/708 of one or more of the interlayers
• CPC Class Codes: C04B 37/021 in a direct manner, e.g. direct copper bonding [DCB]
• CPC Class Codes: H01L 23/49822 Multilayer substrates multilayer metallisation on monolayer substrate H01L23/498
• CPC Class Codes: H01L 23/49827 Via connections through the substrates, e.g. pins going through the substrate, coaxial cables H01L23/49822, H01L23/49833, H01L23/4985, H01L23/49861 take precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/09701 Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H05K 1/0272 Adaptations for fluid transport, e.g. channels, holes
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 2201/0347 Overplating, e.g. for reinforcing conductors or bumps; Plating over filled vias reinforcing the conductive pattern H05K3/24
• CPC Class Codes: H05K 2201/0352 Differences between the conductors of different layers of a multilayer
• CPC Class Codes: H05K 2201/096 Vertically aligned vias, holes or stacked vias
• CPC Class Codes: H05K 3/246 : Reinforcing conductive paste, ink or powder patterns by other methods, e.g. by plating
• CPC Class Codes: H05K 3/4061 : for via connections in inorganic insulating substrates
• CPC Class Codes: H05K 3/4611 : by laminating two or more circuit boards H05K3/4652 takes precedence
• CPC Class Codes: H05K 3/4629 : laminating inorganic sheets comprising printed circuits, e.g. green ceramic sheets
• CPC Class Codes: Y10T 428/24926 : including ceramic, glass, porcelain or quartz layer

Abstract

Disclosed is a multilayer ceramic substrate, and a method for forming same, which has an outer unsealed layer having a metallic via, an inner sealed layer having a composite via of metallic and ceramic materials and a further unsealed layer having a metallic via.

Claims

1. A multilayer ceramic substrate having a sealed layer comprising:

a plurality of layers of ceramic material;

a first layer of the plurality of layers of ceramic material having at least one via filled with a metallic material and substantially no ceramic material;

a second layer of the plurality of layers of ceramic material adjacent to the first layer and having at least one via filled with a material comprising metallic material and ceramic material; and

a third layer of the plurality of layers of ceramic material adjacent to the second layer and having at least one via filled with a metallic material and substantially no ceramic material.

2. The ceramic substrate of claim 1 further comprising a first via cap interposed between the at least one via in the first layer and the at least one via in the second layer.

3. The ceramic substrate of claim 2 wherein the first via cap comprises metallic material and ceramic material.

4. The ceramic substrate of claim 3 wherein the first via cap comprises 60-40 volume percent metallic material and 40-60 volume percent ceramic material.

5. The ceramic substrate of claim 3 wherein the metallic material is copper and the ceramic material is a glass ceramic material.

6. The ceramic substrate of claim 1 further comprising a second via cap interposed between the at least one via in the second layer and the at least one via in the third layer.

7. The ceramic substrate of claim 6 wherein the second via cap comprises metallic material and ceramic material.

8. The ceramic substrate of claim 7 wherein the second via cap comprises 60-40 volume percent metallic material and 40-60 volume percent ceramic material.

9. The ceramic substrate of claim 8 wherein the metallic material is copper and the ceramic material is a glass ceramic material.

10. The ceramic substrate of claim 1 wherein the at least one via in the first layer has a first surface adjacent the second layer and a second surface opposite the first surface and further comprising a plated metallic material on the second surface.

11. The ceramic substrate of claim 10 wherein the plated metallic material on the second surface is selected from the group consisting of nickel and gold.

12. The ceramic substrate of claim 11 further comprising a quantity of solder material on the plated second surface.

13. The ceramic substrate of claim 1 wherein the at least one via in the second layer comprises 60-40 volume percent metallic material and 40-60 volume percent ceramic material.

14. The ceramic substrate of claim 13 wherein the metallic material comprises copper and the ceramic material comprises a glass ceramic material.

15. The ceramic substrate of claim 1 wherein the metallic material in the at least one via in the first layer is copper or an alloy of copper and nickel.

16. The ceramic substrate of claim 15 wherein the alloy of copper and nickel is 90 volume percent copper and 10 volume percent nickel.

17. The ceramic substrate of claim 1 wherein the metallic material in the at least one via in the third layer is copper.

18. The ceramic substrate of claim 1 further comprising a fourth layer of the plurality of layers of ceramic material adjacent to the third layer and having at least one via filled with a metallic material and substantially no ceramic material.

19. The ceramic substrate of claim 18 wherein the metallic material of the at least one via of the fourth layer is copper.

20. The ceramic substrate of claim 1 wherein the first layer is an outermost layer of the ceramic substrate.

21. The ceramic substrate of claim 1 wherein the first layer comprises a top surface metallurgy layer.

22. A multilayer ceramic substrate having a sealed layer comprising:

a plurality of layers of ceramic material;

a first layer of the plurality of layers of ceramic material having at least one via filled with a metallic material and substantially no ceramic material;

a second layer of the plurality of layers of ceramic material adjacent to the first layer and having at least one via filled with a material comprising metallic material and ceramic material;

a first via cap interposed between the at least one via in the first layer and the at least one via in the second layer, the first via cap comprising metallic material and ceramic material;

a third layer of the plurality of layers of ceramic material adjacent to the second layer and having at least one via filled with a metallic material and substantially no ceramic material; and

a second via cap interposed between the at least one via in the second layer and the at least one via in the third layer, the second via cap comprising metallic material and ceramic material.

23. The ceramic substrate of claim 22 wherein the at least one via in the second layer, the first via cap and the second via cap comprise 60-40 volume percent metallic material and 40-60 volume percent ceramic material.

24. The ceramic substrate of claim 23 wherein the metallic material is copper and the ceramic material is a glass ceramic material.

25. The ceramic substrate of claim 22 wherein the metallic material of the at least one via of the first layer is copper or an alloy of copper and nickel.

26. The ceramic substrate of claim 25 wherein the alloy of copper and nickel is 90 volume percent copper and 10 volume percent nickel.

27. The ceramic substrate of claim 22 wherein the metallic material in the at least one via in the third layer is copper.

28. The ceramic substrate of claim 22 wherein the first layer is an outermost layer of the ceramic substrate.

29. The ceramic substrate of claim 22 wherein the first layer comprises a top surface metallurgy layer.