Copper diffusion barrier

• US 8,729,701 B2
• Filed: 09/15/2010
• Issued: 05/20/2014
• Est. Priority Date: 06/24/2005
• Status: Active Grant

• Current Assignee: Stmicroelectronics Crolles 2 SAS (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SAS (STMicroelectronics NV)
• Inventors: Jourdan, Nicolas, Torres, Joaquin
• Primary Examiner(s): WILCZEWSKI, MARY A
• Application Number:
  US12/882,577
• Publication Number:
  US 20110006430A1
• Time in Patent Office: 1,343 Days
• Field of Search: 257/751, 257/758, 257/762, 257/E23.161, 438/687
• US Class Current: 257/751
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76864 Thermal treatment
• CPC Class Codes: H01L 21/76868 Forming or treating discontinuous thin films, e.g. repair, enhancement or reinforcement of discontinuous thin films
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 2221/1089 Stacks of seed layers
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• 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

Abstract

The invention concerns a method of forming a copper portion surrounded by an insulating material in an integrated circuit structure, the insulating material being a first oxide, the method having steps including forming a composite material over a region of the insulating material where the copper portion is to be formed, the composite material having first and second materials, annealing such that the second material reacts with the insulating material to form a second oxide that provides a diffusion barrier to copper; and depositing a copper layer over the composite material by electrochemical deposition to form the copper portion.

Claims

1. An integrated circuit comprising a copper portion in a layer of insulating material, the insulating layer formed of an oxide, said copper portion and said insulating material being separated by a copper diffusion barrier comprising a metal forming a tertiary compound with the insulating material and by a seed-repair layer, wherein said metal and seed-repair layer comprise a deposition of a composition of a first and second material and the first material forms the seed-repair layer for the copper portion, and wherein the first material comprises ruthenium.

2. The integrated circuit of claim 1, wherein said insulating layer and said copper diffusion barrier each comprise silicon oxide.

3. The integrated circuit of claim 1 wherein the diffusion barrier to copper is formed in an edge of the insulating layer adjacent to the copper portion.

4. The integrated circuit of claim 1, wherein the first material comprises approximately 40 to 60 percent of the composition.

5. The integrated circuit of claim 1, wherein the first material is different than the material of the copper portion.

6. The integrated circuit of claim 1, wherein the second material comprises at least one metal selected from the list comprising:

manganese;

titanium;

tantalum;

tungsten; and

aluminium.

7. The integrated circuit of claim 1, wherein the first material forms a conductive oxide.

8. An integrated circuit comprising a copper portion in a layer of insulating material, the insulating layer formed of an oxide, said copper portion and said insulating material being separated by a seed-repair layer comprising a first material and a copper diffusion barrier comprising a second material, wherein the copper diffusion barrier is a tertiary compound formed in an edge of the insulating layer adjacent to the copper portion and the seed-repair layer is disposed between the copper diffusion barrier and the copper portion, wherein the first material comprises ruthenium.

9. The integrated circuit of claim 8, wherein the second material comprises at least one metal selected from the list comprising:

manganese;

titanium;

tantalum;

tungsten; and

aluminium.

10. The integrated circuit of claim 8 further comprising a copper contact electrically coupled to the copper portion through only two interfaces.

11. The integrated circuit of claim 10 wherein the two interfaces are located between the copper portion and a composite material layer and between the composite material layer and the copper contact, wherein the composite material layer comprises the first and second materials.

12. The integrated circuit of claim 8, wherein the first material and second material are deposited as a composition and the second material is reacted with the insulating material to form the tertiary compound.

13. The integrated circuit of claim 12, wherein the first material forms a conductive oxide.

14. The integrated circuit of claim 12, wherein the first material comprises approximately 40 to 60 percent of the composition.

15. The integrated circuit of claim 12, wherein the first material is different than the material of the copper portion.

16. An integrated circuit comprising a copper portion in a layer of insulating material, the insulating layer formed of an oxide, said copper portion and said insulating material being separated by a seed-repair layer comprising a first material and a copper diffusion barrier comprising a second material, wherein the copper diffusion barrier is a tertiary compound formed in an edge of the insulating layer adjacent to the copper portion and the seed-repair layer is disposed between the copper diffusion barrier and the copper portion, wherein the first material and second material are deposited as a composition and the second material is reacted with the insulating material to form the tertiary compound.

17. The integrated circuit of claim 16, wherein the first material comprises ruthenium.

18. The integrated circuit of claim 16, wherein the second material comprises at least one metal selected from the list comprising:

manganese;

titanium;

tantalum;

tungsten; and

aluminium.

19. The integrated circuit of claim 16, further comprising a copper contact electrically coupled to the copper portion through only two interfaces.

20. The integrated circuit of claim 19 wherein the two interfaces are located between the copper portion and a composite material layer and between the composite material layer and the copper contact, wherein the composite material layer comprises the first and second materials.

21. The integrated circuit of claim 16, wherein the first material forms a conductive oxide.

22. The integrated circuit of claim 16, wherein the first material comprises approximately 40 to 60 percent of the composition.

23. The integrated circuit of claim 16, wherein the first material is different than the material of the copper portion.