Two-layer film for next generation damascene barrier application with good oxidation resistance

• US 7,749,563 B2
• Filed: 10/07/2002
• Issued: 07/06/2010
• Est. Priority Date: 10/07/2002
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Nemani, Srinivas D., Zheng, Yi
• Primary Examiner(s): TUROCY, DAVID P
• Application Number:
  US10/266,551
• Publication Number:
  US 20040067308A1
• Time in Patent Office: 2,829 Days
• Field of Search: None
• US Class Current: 427/249.15
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/325 Silicon carbide
• CPC Class Codes: H01L 21/02167 the material being a silicon carbide not containing oxygen, e.g. SiC, SiC:H or silicon carbonitrides H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/314 Inorganic layers H01L21/3105, H01L21/32 take precedence
• CPC Class Codes: H01L 21/7681 involving one or more buried masks
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76832 Multiple layers

Abstract

A method is provided for processing a substrate including providing a processing gas comprising an organosilicon compound comprising a phenyl group to the processing chamber, and reacting the processing gas to deposit a low k silicon carbide barrier layer useful as a barrier layer in damascene or dual damascene applications with low k dielectric materials. A method is provided for depositing a silicon carbide cap layer that has substantially no phenyl groups attached to silicon atoms from a processing gas comprising an oxygen-free organosilicon compound on a low k silicon carbide barrier layer.

Claims

1. A method for processing a substrate, comprising:

forming a barrier layer in a dual damascene structure, wherein the barrier layer is directly formed on a substrate surface comprising metal features, and the forming comprises;

depositing a silicon carbide barrier layer on the substrate by introducing a first processing gas mixture comprising dimethylphenylsilane and a nitrogen containing compound into a processing chamber, and reacting the first processing gas mixture to deposit the silicon carbide barrier layer, wherein the silicon carbide barrier layer has a dielectric constant of less than 4; and

depositing a silicon carbide cap layer directly on the silicon carbide barrier layer by introducing a second processing gas mixture comprising trimethylsilane into the processing chamber, and reacting the second processing gas mixture to deposit the silicon carbide cap layer in the processing chamber, wherein the silicon carbide cap layer has a thickness between about 50 Å

to about 100 Å

.

2. The method of claim 1, wherein the second processing gas mixture further comprises helium.

3. The method of claim 1, wherein the silicon carbide cap layer is deposited under plasma conditions comprising a high frequency RF power density from about 0.02 W/cm² to about 5 W/cm².

4. The method of claim 1, wherein the trimethylsilane of the second processing gas mixture is flowed into the chamber at a flow rate of between about 50 sccm and about 800 sccm.

5. The method of claim 1, wherein the second processing gas mixture further comprises an oxygen-free gas selected from the group of argon, helium, nitrogen, and ammonia.

6. The method of claim 5, wherein the oxygen-free gas of the second processing gas mixture is flowed into the chamber at a flow rate of between about 50 sccm and about 2000 sccm.

7. The method of claim 1, wherein the reacting the first processing gas mixture comprises reacting the dimethylphenylsilane of the first processing gas mixture with an oxygen-containing compound selected from the group of oxygen, ozone, a siloxane, and combinations thereof.

8. The method of claim 1, wherein the first processing gas mixture further includes a dopant component selected from the group of a nitrogen-containing compound, a boron-containing compound, a phosphorus-containing compound, and combinations thereof.

9. The method of claim 8, wherein the nitrogen-containing compound is selected from the group of nitrogen gas, ammonia, a silazane, and combinations thereof.

10. The method of claim 1, wherein the first processing gas mixture further comprises an inert gas selected from the group of argon, helium, neon, xenon, or krypton, and combinations thereof.

11. The method of claim 1, wherein the silicon carbide barrier layer comprises less than about 15 atomic percent of oxygen.

12. The method of claim 1, further comprising depositing a dielectric layer directly on the silicon carbide cap layer, wherein the dielectric layer has a dielectric constant less than about 4.

13. The method of claim 12, wherein the dielectric layer has a carbon content between about 5 and about 30 atomic percent excluding hydrogen atoms.

14. The method of claim 13, wherein the dielectric layer is deposited by oxidizing an organosilane or organosiloxane compound in a plasma enhanced chemical vapor deposition technique.

15. The method of claim 14, wherein the dielectric layer is deposited by reacting trimethylsilane and oxygen in a plasma enhanced chemical vapor deposition technique.

16. The method of claim 15, wherein the dielectric layer is deposited under plasma conditions comprising a high frequency RF power density from about 0.16 W/cm² to about 0.48 W/cm².

17. The method of claim 1, wherein the silicon carbide cap layer has substantially no phenyl groups attached to silicon atoms.

18. A method for processing a substrate, comprising:

forming a barrier layer in a dual damascene structure, wherein the barrier layer is directly formed on a substrate surface comprising metal features, and the forming comprises;

depositing a silicon carbide barrier layer on the substrate by introducing a first processing gas mixture comprising dimethylphenylsilane and a dopant component containing nitrogen into a processing chamber and reacting the first processing gas mixture to deposit the silicon carbide barrier layer, wherein the silicon carbide barrier layer has a dielectric constant of less than 4; and

depositing a silicon carbide cap layer directly on the silicon carbide barrier layer by introducing a second processing gas mixture comprising trimethylsilane into the processing chamber, and reacting the second processing gas mixture to deposit the silicon carbide cap layer in the processing chamber, wherein the silicon carbide cap layer comprises nitrogen, and the silicon carbide cap layer has a thickness between about 50 Å

to about 100 Å

.

19. The method of claim 18, wherein the second processing gas mixture comprises a source of nitrogen.

20. The method of claim 18, wherein the dopant component supplied in the first processing mixture further includes an oxygen-containing compound, a boron-containing compound, a phosphorus-containing compound, and combinations thereof.

21. The method of claim 18, wherein the silicon carbide barrier layer comprises less than about 15 atomic percent of oxygen.

22. The method of claim 18, further comprising depositing a dielectric layer directly on the silicon carbide cap layer, wherein the dielectric layer has a dielectric constant less than about 3.

23. The method of claim 22, wherein the dielectric layer comprises silicon, oxygen, and carbon.

24. The method of claim 23, wherein the dielectric layer is deposited by oxidizing an organosilane or organosiloxane compound in a plasma enhanced chemical vapor deposition technique.

25. The method of claim 18, wherein the silicon carbide cap layer has substantially no phenyl groups attached to silicon atoms.

26. A method for processing a substrate, comprising:

forming a barrier layer in a dual damascene structure, wherein the barrier layer is directly formed on a substrate surface comprising metal features, and the forming comprises;

depositing a silicon carbide barrier layer on the substrate by introducing a first processing gas mixture comprising dimethylphenylsilane and a nitrogen containing gas into a processing chamber and reacting the first processing gas mixture to deposit the silicon carbide barrier layer, wherein the silicon carbide barrier layer has a dielectric constant of less than 4; and

depositing a silicon carbide cap layer directly on the barrier layer by introducing a second processing gas mixture comprising trimethylsilane and ammonia into the processing chamber, and reacting the second processing gas mixture to deposit the silicon carbide cap layer in the processing chamber, wherein the silicon carbide cap layer comprises nitrogen, and the silicon carbide cap layer has a thickness between about 50 Å

to about 100 Å

.

27. The method of claim 26, further comprising depositing a dielectric layer directly on the silicon carbide cap layer, wherein the dielectric layer has a dielectric constant less than about 3.

28. The method of claim 27, wherein the dielectric layer comprises silicon, oxygen, and carbon.

29. The method of claim 28, wherein the dielectric layer is deposited by oxidizing an organosilane or organosiloxane compound in a plasma enhanced chemical vapor deposition technique.

30. The method of claim 26, wherein the silicon carbide cap layer has substantially no phenyl groups attached to silicon atoms.

31. The method of claim 26, wherein the second gas mixture further comprises helium.