Methods for the reduction and elimination of particulate contamination with CVD of amorphous carbon

• US 20060014397A1
• Filed: 07/13/2004
• Published: 01/19/2006
• Est. Priority Date: 07/13/2004
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Seamons, Martin Jay, Yeh, Wendy H., Rathi, Sudha S. R., Botelho, Heraldo L.
• Granted Patent: US 7,094,442 B2
• Time in Patent Office: Days
• US Class Current: 438/778
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C23C 16/4401 Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
• CPC Class Codes: C23C 16/4404 Coatings or surface treatment on the inside of the reaction chamber or on parts thereof
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: H01L 21/02115 the material being carbon, e.g. alpha-C, diamond or hydrogen doped carbon
• 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 21/3146 Carbon layers, e.g. diamond-like layers

Abstract

A method is provided for forming an amorphous carbon layer, deposited on a dielectric material such as oxide, nitride, silicon carbide, carbon doped oxide, etc., or a metal layer such as tungsten, aluminum or poly-silicon. The method includes the use of chamber seasoning, variable thickness of seasoning film, wider spacing, variable process gas flows, post-deposition purge with inert gas, and post-deposition plasma purge, among others, to make the deposition of an amorphous carbon film at low deposition temperatures possible without any defects or particle contamination.

Claims

1. A method for processing a substrate in a chamber, comprising:

depositing a first material for a first deposition time inside the chamber;

positioning a substrate inside the chamber;

providing a gas mixture by flowing one or more hydrocarbon compounds and an inert gas to the chamber;

applying an electric field to the gas mixture and heating the gas mixture to decompose the one or more hydrocarbon compounds in the gas mixture and generate a plasma;

depositing a second material on the substrate for a second deposition time; and

then

terminating at least one gas flow of the one or more hydrocarbon compounds while still flowing the inert gas to the deposition chamber for a first time period, wherein any gas or plasma generated is pumped out of the chamber for a second time period, thereby reducing particle contamination on the substrate.

2. The method of claim 1, further comprising cleaning the chamber with a cleaning plasma before depositing the first material, wherein the cleaning plasma is generated by flowing a cleaning gas into the chamber and applying an electric field.

3. The method of claim 2, wherein the cleaning gas is selected from the group consisting of oxygen-containing gas, hydrogen-containing gas, nitrogen-containing gas, oxygen gas, hydrogen gas, carbon dioxide, nitrous oxide, ammonium, helium, argon, and combinations thereof.

4. The method of claim 1, wherein the first material is an amorphous carbon.

5. The method of claim 1, wherein the second material is an amorphous carbon.

6. The method of claim 1, wherein the substrate is heated to a temperature between about 100°

C. and about 600°

C.

7. The method of claim 1, wherein the first deposition time is between about 5 seconds to about 30 seconds.

8. The method of claim 1, wherein the second deposition time is between about 5 seconds or longer.

9. The method of claim 1, wherein the first time period is between about 5 seconds to about 60 seconds.

10. The method of claim 1, wherein the second time period is between about 5 seconds to about 180 seconds.

11. The method of claim 1, wherein the one or more hydrocarbon compounds comprises the general formula C_xH_y, wherein x has a range of 1 to 8 and y has a range of 2 to 18.

12. The method of claim 1, wherein the one or more hydrocarbon compounds are selected from the group consisting of methane (CH₄), ethane (C₂H₆), ethene (C₂H₄), propylene (C₃H₆), propyne (C₃H₄), propane (C₃H₈), butane (C₄H₁₀), butylene (C₄H₈), butadiene (C₄H₆), acetelyne (C₂H₂), benzene (C₆H₆), methyl benzene (C₇H₈), and combinations thereof.

13. The method of claim 1, wherein the electric field is generated by applying a power source selected from the group consisting of radiofrequency power, microwave frequency, and combinations thereof, and coupling to the deposition chamber in a way selected from the group consisting of inductively coupling, and capacitively coupling.

14. The method of claim 13, wherein the power source is turned off while the at least one gas flow of the one or more hydrocarbon compounds is terminated.

15. The method of claim 1, wherein the inert gas is selected from the group consisting of helium, argon and combinations thereof.

16. The method of claim 1, further comprising moving the substrate to a different distance from a gas distribution system of the chamber after the second material is deposited.

17. A method for processing a substrate in a chamber, comprising:

positioning a substrate inside the chamber;

providing a gas mixture by flowing one or more hydrocarbon compounds and an inert gas to the deposition chamber;

applying an electric field to the gas mixture and heating the gas mixture to decompose the one or more hydrocarbon compounds in the gas mixture and generate a plasma;

depositing a material on the substrate for a deposition time;

moving the substrate to a different distance from a gas distribution system of the chamber; and

then

terminating at least one gas flow of the one or more hydrocarbon compounds while still flowing the inert gas to the deposition chamber for a first time period, wherein any gas or plasma generated is pumped out of the chamber for a second time period, thereby reducing particle contamination on the substrate.

18. The method of claim 17, further comprising cleaning the chamber with a cleaning plasma before positioning the substrate, wherein the cleaning plasma is generated by flowing a cleaning gas into the chamber and applying an electric field.

19. The method of claim 18, wherein the cleaning gas is selected from the group consisting of oxygen-containing gas, hydrogen-containing gas, nitrogen-containing gas, oxygen gas, hydrogen gas, carbon dioxide, nitrous oxide, ammonium, helium, argon, and combinations thereof.

20. The method of claim 17, further comprising depositing the same material inside the chamber before positioning the substrate inside the chamber and depositing the material on the substrate.

21. The method of claim 20, wherein the same material is deposited inside the chamber for a deposition time of between about 5 seconds to about 30 seconds.

22. The method of claim 17, wherein the material is an amorphous carbon.

23. The method of claim 17, wherein the substrate is heated to a temperature between about 100°

C. and about 600°

C.

24. The method of claim 17, wherein the deposition time is between about 5 seconds or longer.

25. The method of claim 17, wherein the first time period is between about 5 seconds to about 1 minute.

26. The method of claim 17, wherein the second time period is between about 5 seconds to about 3 minutes.

27. The method of claim 17, wherein the one or more hydrocarbon compounds comprises the general formula C_xH_y, wherein x has a range of 1 to 8 and y has a range of 2 to 18.

28. The method of claim 17, wherein the one or more hydrocarbon compounds are selected from the group consisting of methane (CH₄), ethane (C₂H₆), ethene (C₂H₄), propylene (C₃H₆), propyne (C₃H₄), propane (C₃H₈), butane (C₄H,₀), butylene (C₄H₈), butadiene (C₄H₆), acetelyne (C₂H₂), benzene (C₆H₆), methyl benzene (C₇H₈), and combinations thereof.

29. The method of claim 17, wherein the electric field is generated by applying a power source selected from the group consisting of radiofrequency power, microwave frequency, and combinations thereof, and coupling to the deposition chamber in a way selected from the group consisting of inductively coupling, and capacitively coupling.

30. The method of claim 29, wherein the power source is turned off while the at least one gas flow of the one or more hydrocarbon compounds is terminated.

31. The method of claim 29, wherein the power source is still turned on while the at least one gas flow of the one or more hydrocarbon compounds is terminated.

32. The method of claim 17, wherein the inert gas is selected from the group consisting of helium, argon and combinations thereof.

33. The method of claim 17, wherein the substrate is moved to a different distance from a gas distribution system to be close to an exhaust of the chamber.

34. The method of claim 17, wherein the substrate is moved to a loading/unloading position.

35. A method for depositing an amorphous carbon material on a substrate in a chamber, comprising:

depositing a first material for a first deposition time inside the chamber;

positioning a substrate inside the chamber;

providing a gas mixture by flowing one or more hydrocarbon compounds and an inert gas to the chamber;

applying an electric field to the gas mixture and heating the gas mixture to decompose the one or more hydrocarbon compounds in the gas mixture and generate a plasma;

depositing the amorphous carbon material on the substrate for a second deposition time, thereby reducing particle contamination on the substrate.

36. The method of claim 35, further comprising cleaning the chamber with a cleaning plasma before depositing the first material, wherein the cleaning plasma is generated by flowing a cleaning gas into the chamber and applying an electric field.

37. The method of claim 36, wherein the cleaning gas is selected from the group consisting of oxygen-containing gas, hydrogen-containing gas, nitrogen-containing gas, oxygen gas, hydrogen gas, carbon dioxide, nitrous oxide, ammonium, helium, argon, and combinations thereof.

38. The method of claim 35, wherein the first material is an amorphous carbon.

39. The method of claim 35, wherein the substrate is heated to a temperature between about 100°

C. and about 600°

C.

40. The method of claim 35, further comprising moving the substrate to a different distance from a gas distribution system of the chamber.

41. The method of claim 40, wherein the substrate is moved to a different distance from the gas distribution system to be close to an exhaust of the chamber.

42. The method of claim 40, wherein the substrate is moved to a loading/unloading position.

43. The method of claim 35, further comprising terminating at least one gas flow of the one or more hydrocarbon compounds while still flowing the inert gas to the deposition chamber.

44. The method of claim 43, wherein the electric field is still on while the at least one gas flow of the one or more hydrocarbon compounds is terminated.

45. The method of claim 43, wherein the electric field is turned off while the at least one gas flow of the one or more hydrocarbon compounds is terminated.

46. The method of claim 35, wherein the inert gas is selected from the group consisting of helium, argon and combinations thereof.

47. The method of claim 35, further comprising pumping any gas or plasma generated out of the chamber.

48. The method of claim 35, wherein the one or more hydrocarbon compounds comprises the general formula C_xH_y, wherein x has a range of 1 to 8 and y has a range of 2 to 18.

49. The method of claim 48, wherein the one or more hydrocarbon compounds are selected from the group consisting of methane (CH₄), ethane (C₂H₆), ethene (C₂H₄), propylene (C₃H₆), propyne (C₃H₄), propane (C₃H₈), butane (C₄H₁₀), butylene (C₄H₈), butadiene (C₄H₆), acetelyne (C₂H₂), benzene (C₆H₆), methyl benzene (C₇H₈), and combinations thereof.