Packaging of electronic chips with air-bridge structures

• US 7,335,965 B2
• Filed: 09/01/2004
• Issued: 02/26/2008
• Est. Priority Date: 08/25/1999
• Status: Expired due to Fees

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Farrar, Paul A.
• Primary Examiner(s): Graybill; David E
• Application Number:
  US10/931,510
• Publication Number:
  US 20050026351A1
• Time in Patent Office: 1,273 Days
• Field of Search: None
• US Class Current: 257/522
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 23/20 gaseous at the normal operating temperature of the device
• CPC Class Codes: H01L 23/3677 Wire-like or pin-like cooling fins or heat sinks
• CPC Class Codes: H01L 23/4821 Bridge structure with air gap
• CPC Class Codes: H01L 23/5222 Capacitive arrangements or effects of, or between wiring layers other capacitive arrangements H01L23/642
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 23/66 High-frequency adaptations
• 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 2924/1433 Application-specific integrated circuit [ASIC]
• CPC Class Codes: Y10S 438/977 Thinning or removal of substrate

Abstract

A circuit assembly for fabricating an air bridge structure and a method of fabricating an integrated circuit package capable of supporting a circuit assembly including an air bridge structure. A circuit assembly comprises an electronic chip and a conductive structure embedded in a plurality of materials having a plurality of vaporization temperatures. The plurality of materials is formed on the electronic chip and the conductive structure is coupled to the electronic chip. To fabricate the circuit assembly, a support structure, including interstices, is formed on an electronic chip. The interstices of the support structure are filled with a material having a vaporization temperature that is less than the vaporization temperature of the support structure. Conductive structures are embedded in the support structure and the material, and a connective structure is mounted on the support structure. Finally, the material is removed from the interstices by heating the circuit assembly.

Claims

1. An integrated circuit assembly comprising:

an electronic chip;

a support structure mounted on the electronic chip, the support structure having an interstice and a vaporization temperature;

a material filling the interstice, the material having a vaporization temperature that is less than the vaporization temperature of the support structure;

a connective structure mounted on the support structure, wherein the connective structure is a controlled collapse chip connection (C4) structure; and

a conductive structure capable of coupling the electronic chip to the connective structure, the conductive structure embedded in the support structure and the material and in contact with the material filling the interstice.

2. The integrated circuit assembly of claim 1, wherein the electronic chip is a dynamic random access memory chip.

3. The integrated circuit assembly of claim 1, wherein the support structure is fabricated from silicon dioxide.

4. The integrated circuit assembly of claim 1, wherein the support structure is a ribbed structure.

5. The integrated circuit assembly of claim 1, wherein the conductive structure is fabricated from a copper alloy.

23. The integrated circuit assembly of claim 1, wherein the material includes carbon.

6. An integrated circuit memory device comprising:

an electronic memory chip; and

a non-conductive ribbed structure mounted on the electronic memory chip and capable of protecting an air-bridge structure and supporting a C4 structure.

7. The integrated circuit memory device of claim 6, wherein the ribbed structure is fabricated from an inorganic insulator.

8. The integrated circuit memory device of claim 6, wherein the ribbed structure is fabricated from an organic material.

9. The integrated circuit memory device of claim 6, wherein the ribbed structure is fabricated from of a mix of organic and inorganic materials.

24. The integrated circuit memory device of claim 6, wherein the ribbed structures includes one or more interstices.

25. The integrated circuit memory device of claim 24, wherein the one or more interstices include fill material.

26. The integrated circuit memory device of claim 25, wherein the fill material includes carbon.

10. An integrated circuit assembly comprising:

an electronic chip including a plurality of electronic devices;

a material layer on a surface of the electronic chip, the material layer having a ribbed structure having a depth and forming one or more interstices,

a plurality of conductive segments including at least one air-bridge structure having a horizontal conductive interconnect within the material layer and above and not in contact with the surface of the electronic chip and at least one vertical wiring via coupling the horizontal conductive interconnect to one or more of the plurality of electronic devices;

a C4 structure including an insulating layer formed above the ribbed structure, above the conductive segments, and above the interstices, and coupled to the electronic chip through a plurality of conductive elements coupled to one or more of the plurality of conductive segments; and

a substrate coupled to the C4 structure.

11. The integrated circuit assembly of claim 10, wherein the integrated circuit assembly is hermetically sealed.

12. The integrated circuit assembly of claim 11, wherein the integrated circuit assembly is back filled with helium.

13. The integrated circuit assembly of claim 11, wherein the integrated circuit assembly is back filled with a helium rich gas mixture.

14. The integrated circuit assembly of claim 10, wherein the material is air.

15. The integrated circuit assembly of claim 10, further comprising a heat sink coupled to the electronic chip.

16. The integrated circuit assembly of claim 15, wherein the integrated circuit assembly is hermetically sealed.

17. The integrated circuit assembly of claim 16, wherein the integrated circuit assembly is back filled with helium.

31. The integrated circuit assembly of claim 10, wherein the horizontal conductive interconnect is embedded in a material including carbon.

32. The integrated circuit assembly of claim 10, wherein the electronic chip is a memory chip.

35. The integrated circuit assembly of claim 10, wherein the insulating layer of the C4 structure is in contact with the support structure.

36. The integrated circuit assembly of claim 35, wherein the ribbed structure includes silicon nitride.

18. A computer system comprising:

a processor;

a memory device having a plurality of circuit devices, the memory device coupled to the processor; and

an air-bridge structure and a support structure fabricated on the memory device, the air-bridge structure capable of coupling at least two of the plurality of circuit devices and the support structure capable of supporting the memory device mounted as a flip chip,

wherein the support structure includes a ribbed structure formed on a surface of the memory device and having a depth about equal to a distance from a surface of the memory device to a wiring layer, the air bridge structure having a horizontal conductive interconnect above and not in contact with the surface of the memory device and at least one vertical wiring via coupling the horizontal conductive interconnect to one or more of the plurality of circuit devices.

19. The computer system of claim 18, wherein the air-bridge structure is embedded in a dielectric having a dielectric constant of about 1.

20. The computer system of claim 18, wherein the support structure is designed to support the entire weight of the memory device.

27. The computer system of claim 18, wherein the support structure is embedded in a material layer.

28. The computer system of claim 27, wherein the material layer includes carbon.

37. The computer system of claim 18, wherein the ribbed structure includes silicon nitride.

21. An integrated circuit assembly comprising:

an electronic chip;

a plurality of material that includes a support structure having a plurality of elongate support members that are approximately parallel to one of the sides of the electronic chip; and

a plurality of conductive structures embedded in the plurality of materials, each of the plurality of materials having a different vaporization temperature, the plurality of materials is formed on the electronic chip, wherein the plurality of conductive structures are coupled to the electronic chip, and at least one of the plurality of conductive structures is free from contact with any portion of the plurality of elongate support members.

29. The integrated circuit assembly of claim 21, wherein at least one of the plurality of materials is carbon.

33. The integrated circuit assembly of claim 21, wherein the electronic chip is a memory chip.

38. The integrated circuit assembly of claim 21, wherein the support structure includes a ribbed structure.

22. An integrated circuit assembly comprising:

an electronic chip;

a ribbed support structure mounted on the electronic chip, the ribbed support structure having a vaporization temperature, wherein the ribbed support structure comprises a number of support members, wherein the number of support members are parallel to one of the sides of the electronic chip and are approximately the length of the electronic chip, the number of support members arranged to create a plurality of interstices;

a material filling one or more of the plurality of interstices, the material having a vaporization temperature that is less than the vaporization temperature of the ribbed support structure;

a controlled collapse chip connection (C4) connective structure mounted on the ribbed support structure, wherein the C4 structure is to mount on a silicon substrate; and

a conductive structure capable of coupling the electronic chip to the connective structure, the conductive structure embedded in the ribbed support structure and the material.

30. The integrated circuit assembly of claim 22, wherein the material includes carbon.

34. The integrated circuit assembly of claim 22, wherein the electronic chip is a memory chip.