COBALT DEPOSITION ON BARRIER SURFACES

• US 20090053426A1
• Filed: 08/29/2008
• Published: 02/26/2009
• Est. Priority Date: 07/25/2001
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: LU, JIANG, Ha, Hyoung-Chan, Ganguli, Seshadri, Yu, Sang Ho, Ma, Paul, Aubuchon, Joseph F., Narasimhan, Murali K.
• Granted Patent: US 9,051,641 B2
• Time in Patent Office: Days
• US Class Current: 427/540
• CPC Class Codes: C23C 16/16 from metal carbonyl compounds
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/42 Silicides
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/28568 the conductive layers comprising transition metals H01L21/28518 takes precedence
• CPC Class Codes: H01L 21/76846 Layer combinations
• 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 21/76871 Layers specifically deposited to enhance or enable the nucleation of further layers, i.e. seed layers
• CPC Class Codes: H01L 21/76873 for electroplating

Abstract

Embodiments of the invention provide processes for depositing a cobalt layer on a barrier layer and subsequently depositing a conductive material, such as copper or a copper alloy, thereon. In one embodiment, a method for depositing materials on a substrate surface is provided which includes forming a barrier layer on a substrate, exposing the substrate to dicobalt hexacarbonyl butylacetylene (CCTBA) and hydrogen to form a cobalt layer on the barrier layer during a vapor deposition process (e.g., CVD or ALD), and depositing a conductive material over the cobalt layer. In some examples, the barrier layer and/or the cobalt layer may be exposed to a gas or a reagent during a treatment process, such as a thermal process, an in situ plasma process, or a remote plasma process.

Claims

1. A method for depositing materials on a substrate surface, comprising:

forming a barrier layer on a substrate;

exposing the substrate to dicobalt hexacarbonyl butylacetylene (CCTBA) and hydrogen to form a cobalt layer on the barrier layer during a vapor deposition process; and

depositing a conductive material over the cobalt layer.

2. The method of claim 1, further comprising exposing the barrier layer or the cobalt layer to a plasma during a treatment process, wherein the plasma comprises a reagent selected from the group consisting of nitrogen (N₂), ammonia (NH₃), hydrogen (H₂), an ammonia/hydrogen mixture, derivatives thereof, and combinations thereof.

3. The method of claim 2, wherein the barrier layer or the cobalt layer is exposed to a hydrogen plasma for a time period within a range from about 20 seconds to about 40 seconds and the hydrogen plasma is formed by a remote plasma source.

4. The method of claim 1, further comprising exposing the barrier layer or the cobalt layer to a gas during a thermal treatment process, wherein the gas is selected from the group consisting of nitrogen (N₂), ammonia (NH₃), hydrogen (H₂), an ammonia/hydrogen mixture, derivatives thereof, and combinations thereof.

5. The method of claim 4, wherein the substrate is heated to a temperature within a range from about 50°

C. to about 400°

C. during the thermal treatment process.

6. The method of claim 1, wherein the substrate is exposed to a deposition gas comprising the CCTBA and the hydrogen during a thermal chemical vapor deposition process.

7. The method of claim 6, wherein the substrate is heated to a temperature within a range from about 100°

C. to about 250°

C. during the thermal chemical vapor deposition process.

8. The method of claim 1, wherein the substrate is sequentially exposed to the CCTBA and the hydrogen during an atomic layer deposition process.

9. The method of claim 1, wherein the barrier layer comprises tantalum, tantalum nitride, titanium, titanium nitride, tungsten, tungsten nitride, alloys thereof, derivatives thereof, and combinations thereof.

10. The method of claim 9, wherein the barrier layer comprises a tantalum nitride layer disposed on a tantalum layer.

11. The method of claim 1, wherein the conductive material comprises copper or a copper alloy.

12. The method of claim 11, wherein the conductive material comprises a seed layer and a bulk layer.

13. The method of claim 12, wherein the seed layer comprises copper and is deposited by a physical vapor deposition process or a chemical vapor deposition process.

14. The method of claim 12, wherein the bulk layer comprises copper and is deposited by an electrochemical plating process.

15. The method of claim 11, wherein the conductive material is directly deposited on the cobalt layer by an electrochemical plating process.

16. A method for depositing materials on a substrate surface, comprising:

forming a barrier layer on a substrate;

exposing the barrier layer to a first plasma during a pre-treatment process;

exposing the substrate to dicobalt hexacarbonyl butylacetylene (CCTBA) and hydrogen to form a cobalt layer on the barrier layer during a vapor deposition process;

exposing the cobalt layer to a second plasma during a post-treatment process; and

depositing a copper layer on the cobalt layer by a vapor deposition process.

17. The method of claim 16, wherein the first plasma or the second plasma independently comprises a gas selected from the group consisting of nitrogen (N₂), ammonia (NH₃), hydrogen (H₂), argon, helium, an ammonia/hydrogen mixture, derivatives thereof, and combinations thereof.

18. The method of claim 17, wherein the barrier layer is exposed to the first plasma or the cobalt layer is exposed to the second plasma for a time period within a range from about 20 seconds to about 40 seconds, and the first and second plasmas are formed by a remote plasma source.

19. The method of claim 16, wherein the substrate is exposed to a deposition gas comprising the CCTBA and the hydrogen during a thermal chemical vapor deposition process.

20. The method of claim 19, wherein the substrate is heated to a temperature within a range from about 100°

C. to about 250°

C. during the thermal chemical vapor deposition process.

21. The method of claim 16, wherein the substrate is sequentially exposed to the CCTBA and the hydrogen during an atomic layer deposition process.

22. The method of claim 16, wherein the cobalt layer is formed during a plasma-enhanced chemical vapor deposition process or a plasma-enhanced atomic layer deposition process.

23. The method of claim 16, wherein the barrier layer comprises tantalum, tantalum nitride, titanium, titanium nitride, tungsten, tungsten nitride, alloys thereof, derivatives thereof, and combinations thereof.

24. The method of claim 23, wherein the barrier layer comprises a tantalum nitride layer disposed on a tantalum layer.

25. A method for depositing materials on a substrate surface, comprising:

forming a barrier layer on a substrate;

exposing the barrier layer to a plasma during a pre-treatment process;

exposing the substrate to dicobalt hexacarbonyl butylacetylene (CCTBA) and a reducing gas to form a cobalt layer on the barrier layer during a vapor deposition process;

exposing the cobalt layer to a hydrogen plasma during a post-treatment process; and

depositing a copper material over the cobalt layer.