Side wall passivation films for damascene cu/low k electronic devices

• US 20040092095A1
• Filed: 11/12/2002
• Published: 05/13/2004
• Est. Priority Date: 11/12/2002
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Nguyen, Son Van, Nemani, Srinivas D.
• Granted Patent: US 6,878,620 B2
• Time in Patent Office: Days
• US Class Current: 438/627
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• CPC Class Codes: H01L 21/76844 Bottomless liners

Abstract

Methods and apparatus for protecting the dielectric layer sidewalls of openings, such as vias and trenches, in semiconductor substrates are provided. A pre-liner and a liner are deposited over the sidewalls of the openings as part of integrated processing sequences that either do not remove the photoresist until subsequent processing or remove the photoresist with a plasma etch that does not contaminate the sidewalls of the openings.

Claims

1. A method for processing a substrate having a patterned photoresist thereon, comprising:

etching a barrier layer and a low k dielectric layer of the substrate using the patterned photoresist as a mask to form an opening having sidewalls and extending through the barrier layer and the low k dielectric layer to an underlying metal feature or metal layer of the substrate;

depositing a pre-liner on the substrate, wherein the pre-liner is deposited over the photoresist and the sidewalls of the opening, and wherein the pre-liner is selected from the group consisting of oxygen-doped silicon carbide, oxygen and nitrogen-doped silicon carbide, silicon carbide, silicon nitride, silicon dioxide, silicon oxynitride, silicon, aluminum oxide, and combinations thereof;

depositing a liner selected from the group consisting of tantalum, tantalum nitride, tungsten, tungsten nitride, platinum, ruthenium, and combinations thereof on the pre-liner;

removing the photoresist, the pre-liner, and the liner from horizontal surfaces of the substrate; and

then depositing a seed layer on the substrate.

2. The method of claim 1, further comprising cleaning the substrate after the etching a barrier layer and a dielectric layer.

3. The method of claim 1, wherein the etching a barrier layer and a low k dielectric layer comprises a reactive ion etch.

4. The method of claim 1, wherein the depositing a pre-liner comprises a conformal deposition process.

5. The method of claim 1, wherein the depositing a liner comprises a vapor deposition process.

6. The method of claim 1, wherein the removing the photoresist comprises an anisotropic etch process.

7. The method of claim 1, further comprising introducing the substrate having a patterned photoresist thereon into an integrated processing system before the etching a barrier layer and a low k dielectric layer, wherein the substrate is not removed from the integrated processing system until after the depositing a seed layer.

8. The method of claim 7, wherein the etching a barrier layer and a low k dielectric layer is performed in a first processing chamber of the integrated processing system, the depositing a pre-liner is performed in a second processing chamber of the integrated processing system, the removing the photoresist is performed in a third processing chamber of the integrated processing system, and the depositing a seed layer is performed in a fourth processing chamber of the integrated processing system.

9. A method for processing a substrate having a patterned photoresist thereon, comprising:

etching a barrier layer and a low k dielectric layer of the substrate using the patterned photoresist as a mask to form an opening having sidewalls and extending through the barrier layer and the low k dielectric layer to an underlying metal feature or metal layer of the substrate;

removing the photoresist from the low k dielectric layer with a hydrogen plasma, an oxygen-containing plasma, or a combination thereof;

depositing a pre-liner on the low k dielectric layer, wherein the pre-liner is selected from the group consisting of oxygen-doped silicon carbide, oxygen and nitrogen-doped silicon carbide, silicon carbide, silicon nitride, silicon dioxide, silicon oxynitride, silicon, aluminum oxide, and combinations thereof;

depositing a liner selected from the group consisting of tantalum, tantalum nitride, tungsten, tungsten nitride, platinum, ruthenium, and combinations thereof on the pre-liner;

removing the pre-liner and the liner from horizontal surfaces of the substrate;

and then depositing a seed layer on the substrate.

10. The method of claim 9, further comprising cleaning the substrate after the removing the photoresist.

11. The method of claim 9, wherein the etching a barrier layer and a low k dielectric layer comprises a reactive ion etch.

12. The method of claim 9, wherein the depositing a pre-liner comprises a conformal deposition process.

13. The method of claim 9, wherein the depositing a liner comprises a vapor deposition process.

14. The method of claim 9, further comprising introducing the substrate having a patterned photoresist thereon into an integrated processing system before the etching a barrier layer and a low k dielectric layer, wherein the substrate is not removed from the integrated processing system until after the depositing a seed layer.

15. The method of claim 14, wherein the etching a barrier layer and a low k dielectric layer is performed in a first processing chamber of the integrated processing system, the removing the photoresist is performed in a second processing chamber of the integrated processing system, the depositing a pre-liner is performed in a third processing chamber of the integrated processing system, and the depositing a seed layer is performed in a fourth processing chamber of the integrated processing system.

16. The method of claim 14, wherein the etching a barrier layer and a low k dielectric layer and the removing the photoresist are performed in a first processing chamber of the integrated processing system, the depositing a pre-liner is performed in a second processing chamber of the integrated processing system, and the depositing a seed layer is performed in a third processing chamber of the integrated processing system.

17. A computer storage medium containing software that, when executed, causes a computer to perform an operation in an integrated substrate processing system, the operation comprising:

introducing a substrate having a patterned photoresist thereon into an integrated substrate processing system;

etching a barrier layer and a low k dielectric layer of the substrate using the patterned photoresist as a mask through to an underlying metal feature or metal layer of the substrate to form a hole having sidewalls;

depositing a pre-liner on the substrate, wherein the pre-liner is deposited over the photoresist, the sidewalls, and the bottom of the hole, and wherein the pre-liner is selected from the group consisting of oxygen-doped silicon carbide, oxygen and nitrogen-doped silicon carbide, silicon carbide, silicon nitride, silicon dioxide, silicon oxynitride, silicon, aluminum oxide, and combinations thereof;

depositing a liner selected from the group consisting of tantalum, tantalum nitride, tungsten, tungsten nitride, platinum, ruthenium, and combinations thereof on the pre-liner;

removing the photoresist from the substrate;

removing the pre-liner and liner from horizontal surfaces of the substrate; and

then

depositing a seed layer on the substrate, wherein the substrate is not removed from the integrated processing system until after the depositing a seed layer.

18. The computer storage medium of claim 17, wherein the operation further comprises cleaning the substrate after the etching a barrier layer and a dielectric layer.

19. The computer storage medium of claim 17, wherein the etching a barrier layer and a low k dielectric layer comprises a reactive ion etch.

20. The computer storage medium of claim 17, wherein the depositing a pre-liner comprises a conformal deposition process.

21. The computer storage medium of claim 17, wherein the depositing a liner comprises a vapor deposition process.

22. The computer storage medium of claim 17, wherein the removing the photoresist comprises an anisotropic etching process.

23. The computer storage medium of claim 17, wherein the etching a barrier layer and a low k dielectric layer is performed in a first processing chamber of the integrated processing system, the depositing a pre-liner is performed in a second processing chamber of the integrated processing system, the removing the photoresist is performed in a third processing chamber of the integrated processing system, and the depositing a seed layer is performed in a fourth processing chamber of the integrated processing system.

24. A computer storage medium containing software that, when executed, causes a computer to perform an operation in an integrated substrate processing system, the operation comprising:

introducing a substrate having a patterned photoresist thereon into an integrated processing system;

etching a barrier layer and a low k dielectric layer of the substrate using the patterned photoresist as a mask to form an opening having sidewalls and extending through the barrier layer and the low k dielectric layer to an underlying metal feature or metal layer of the substrate;

removing the photoresist from the low k dielectric layer with a hydrogen plasma and/or an oxygen-containing plasma;

depositing a pre-liner on the low k dielectric layer, wherein the pre-liner is selected from the group consisting of oxygen-doped silicon carbide, oxygen and nitrogen-doped silicon carbide, silicon carbide, silicon nitride, silicon dioxide, silicon oxynitride, silicon, aluminum oxide, and combinations thereof;

depositing a liner selected from the group consisting of tantalum, tantalum nitride, tungsten, tungsten nitride, platinum, ruthenium, and combinations thereof on the pre-liner;

removing the pre-liner and the liner from horizontal surfaces of the substrate; and

then

depositing a seed layer on the substrate, wherein the substrate is not removed from the integrated processing system until after the depositing a seed layer.

25. The computer storage medium of claim 24, wherein the operation further comprises cleaning the substrate after the removing the photoresist.

26. The computer storage medium of claim 24, wherein the etching a barrier layer and a low k dielectric layer comprises a reactive ion etch.

27. The computer storage medium of claim 24, wherein the depositing a pre-liner comprises a conformal deposition process.

28. The computer storage medium of claim 24, wherein the depositing a liner comprises a vapor deposition process.

29. The computer storage medium of claim 24, wherein the etching a barrier layer and a low k dielectric layer is performed in a first processing chamber of the integrated processing system, the removing the photoresist is performed in a second processing chamber of the integrated processing system, the depositing a pre-liner is performed in a third processing chamber of the integrated processing system, and the depositing a seed layer is performed in a fourth processing chamber of the integrated processing system.

30. The computer storage medium of claim 24, wherein the etching a barrier layer and a low k dielectric layer and the removing the photoresist are performed in a first processing chamber of the integrated processing system, the depositing a pre-liner is performed in a second processing chamber of the integrated processing system, and the depositing a seed layer is performed in a third processing chamber of the integrated processing system.