Anneal of ruthenium seed layer to improve copper plating

• US 7,442,267 B1
• Filed: 11/29/2004
• Issued: 10/28/2008
• Est. Priority Date: 11/29/2004
• Status: Expired due to Fees

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Inventors: Reid, Jonathan D., Webb, Eric G., Park, Seyang, Sukamto, Johanes H.
• Primary Examiner(s): WYSZOMIERSKI, GEORGE P
• Application Number:
  US10/999,838
• Time in Patent Office: 1,429 Days
• Field of Search: 148/578, 148/678
• US Class Current: 148/518
• CPC Class Codes: C22F 1/14 of noble metals or alloys based thereon
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/76862 Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76864 Thermal treatment
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 21/76874 for electroless plating

Abstract

A ruthenium-containing thin film is formed. Typically, the ruthenium-containing thin film has a thickness in a range of about from 1 nm to 20 nm. The ruthenium-containing thin film is annealed in an oxygen-free atmosphere, for example, in N₂ forming gas, at a temperature in a range of about from 100° C. to 500° C. for a total time duration of about from 10 seconds to 1000 seconds. Thereafter, copper or other metal is deposited by electroplating or electroless plating onto the annealed ruthenium-containing thin film. In some embodiments, the ruthenium-containing thin film is also treated by UV radiation.

Claims

1. A method of treating a ruthenium-containing thin film during integrated circuit fabrication, comprising processes of:

providing a ruthenium-containing thin film located on a substrate, said ruthenium-containing thin film having a thickness in a range of about from 1 nm to 20 nm; and

annealing said ruthenium-containing thin film in an oxygen-free environment under oxide-reducing conditions to form a substantially oxide-free annealed ruthenium-containing thin film.

2. A method as in claim 1, wherein said processes of annealing are conducted before depositing metal on said annealed ruthenium-containing thin film.

3. A method as in claim 1, further comprising processes of applying UV radiation to said annealed ruthenium-containing thin film before depositing metal on said annealed ruthenium-containing thin film.

4. A method as in claim 1, further comprising processes of applying UV radiation to said ruthenium-containing thin film before said processes of annealing.

5. A method as in claim 1, further comprising processes of applying UV radiation to said ruthenium-containing thin film during said processes of annealing.

6. A method as in claim 1, wherein said ruthenium-containing thin film comprises substantially ruthenium atoms.

7. A method as in claim 1, wherein said ruthenium-containing thin film has a thickness in a range of about from 1 nm to 10 nm.

8. A method as in claim 1, wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature in a range of about from 100°

C. to 500°

C. for a total time period in a range of about from 10 seconds to 1000 seconds.

9. A method as in claim 1, wherein said processes of annealing are conducted in forming gas.

10. A method as in claim 1, further comprising processes of moving said ruthenium-containing thin film on said substrate into an anneal chamber before said processes of annealing.

11. A method as in claim 10, further comprising processes of removing gas from said anneal chamber before said processes of annealing to form said oxygen-free environment.

12. A method as in claim 11, wherein said processes of removing gas from said anneal chamber comprise flowing an oxygen-free gas through said anneal chamber.

13. A method as in claim 12, wherein said flowing an oxygen-free gas comprises flowing nitrogen gas.

14. A method of forming a ruthenium-containing thin film, comprising processes of:

depositing a ruthenium-containing thin film to a thickness in a range of about 1 nm to 20 nm on a substrate; and

annealing said ruthenium-containing thin film in an oxygen-free environment under oxide-reducing conditions to form a substantially oxide-free annealed ruthenium-containing thin film.

15. A method as in claim 14, wherein said processes of depositing a ruthenium-containing thin film comprise depositing substantially ruthenium atoms.

16. A method as in claim 14, wherein said processes of depositing a ruthenium-containing thin film comprise depositing a ruthenium-containing thin-film having a thickness in a range of about from 1 nm to 10 nm.

17. A method as in claim 14, wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature in a range of about from 100°

C. to 500°

C. for a total time period in a range of about from 10 seconds to 1000 seconds.

18. A method as in claim 14, wherein said processes of depositing a ruthenium-containing thin film on a substrate comprise depositing said ruthenium-containing thin film on dielectric material.

19. A method as in claim 14, wherein said processes of depositing a ruthenium-containing thin film on a substrate comprise depositing said ruthenium-containing thin film on metal nitride material.

20. A method of plating metal in an integrated circuit, comprising processes of:

providing a ruthenium-containing thin film on a substrate;

annealing said ruthenium-containing thin film in an oxygen-free environment under oxide-reducing conditions to form a substantially oxide-free annealed ruthenium-containing thin film; and

plating metal directly onto said annealed ruthenium-containing thin film.

21. A method as in claim 20, further comprising processes of applying UV radiation to said annealed ruthenium-containing thin film before plating metal on said annealed ruthenium-containing thin film.

22. A method as in claim 20, wherein said ruthenium-containing thin film comprises substantially ruthenium atoms.

23. A method as in claim 20, wherein said ruthenium-containing thin film has a thickness in a range of about from 1 nm to 50 nm.

24. A method as in claim 23, wherein said ruthenium-containing thin film has a thickness in a range of about from 1 nm to 20 nm.

25. A method as in claim 24 wherein said ruthenium-containing thin film has a thickness in a range of about from 1 nm to 10 nm.

26. A method as in claim 20, wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature in a range of about from 100°

C. to 500°

C. for a total time period in a range of about from 10 seconds to 1000 seconds.

27. A method as in claim 26 wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature not exceeding 400°

C.

28. A method as in claim 26 wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature not exceeding 250°

C.

29. A method as in claim 26 wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment at a temperature not exceeding 150°

C.

30. A method as in claim 26 wherein said processes of annealing said ruthenium-containing thin film comprise annealing said ruthenium-containing thin film in an oxygen-free environment for a total time period not exceeding 100 seconds.

31. A method as in claim 20, wherein said processes of annealing are conducted less than 24 hours before said processes of plating metal.

32. A method as in claim 31, wherein said processes of annealing are conducted less than 3 hours before said processes of plating metal.

33. A method as in claim 32, wherein said processes of annealing are conducted less than 1 hour before said processes of plating metal.

34. A method as in claim 33, wherein said processes of annealing are conducted less than five minutes before said processes of plating metal.

35. A method as in claim 20, wherein said processes of plating metal comprise electroplating metal.

36. A method as in claim 20, wherein said processes of plating metal comprise electroless plating of metal.

37. A method as in claim 20, further comprising processes of storing said annealed ruthenium-containing thin film in an oxygen-free space before said processes of plating metal.

38. A method as in claim 20, further comprising processes of limiting exposure to oxidizing conditions of said annealed ruthenium-containing thin film before said plating processes to less than three hours.

39. A method as in claim 38, wherein said processes of limiting exposure to oxidizing conditions before said plating processes limits exposure to less than one hour.

40. A method as in claim 39, wherein said processes of limiting exposure to oxidizing conditions before said plating processes limits exposure to less than five minutes.

41. A method as in claim 20, wherein said processes of plating metal comprise plating copper.

42. A method as in claim 20, wherein said processes of plating metal comprise plating a metal selected from the group consisting of copper, cobalt, nickel, and tantalum.

43. A method as in claim 20, wherein said processes of providing a ruthenium-containing thin film on a substrate comprise providing said ruthenium-containing thin film on a dielectric substrate.