Cycling deposition of low temperature films in a cold wall single wafer process chamber

• US 20030059535A1
• Filed: 09/25/2001
• Published: 03/27/2003
• Est. Priority Date: 09/25/2001
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ahn, Sang Hoon, Wang, Shulin, Luo, Lee, Chen, Aihua, Singh Thakur, Randhir P., Iyer, Ramaseshan Suryanarayanan
• Application Number:
  US09/964,075
• Publication Number:
  US 20030059535A1
• Time in Patent Office: Days
• US Class Current: 427/255.28
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]

Abstract

A method for film deposition that includes, flowing a first reactive gas over a top surface of a wafer in a cold wall single wafer process chamber to form a first half-layer of the film on the wafer, stopping the flow of the first reactive gas, removing residual first reactive gas from the cold wall single wafer process chamber, flowing a second reactive gas over the first half-layer to form a second half-layer of the film where deposition of the second half-layer is non self-limiting, controlling a thickness of the second half-layer by regulating process parameters within the cold wall single wafer process chamber, stopping the flow of the second reactive gas; and removing residual second reactive gas from the cold wall single wafer process chamber.

Claims

1. A method for film deposition, comprising:

flowing a first reactive gas over a top surface of a wafer in a cold wall single wafer process chamber to form a first half-layer of the film on the wafer;

stopping the flow of the first reactive gas;

removing residual first reactive gas from the cold wall single wafer process chamber;

flowing a second reactive gas over the first half-layer to form a second half-layer of the film where deposition of the second half-layer is non self-limiting;

controlling a thickness of the second half-layer by regulating process parameters within the cold wall single wafer process chamber;

stopping the flow of the second reactive gas; and

removing residual second reactive gas from the cold wall single wafer process chamber.

2. The method of claim 1, wherein the first reactive gas may be chosen from the group consisting of N source gas, O source gas, and N/O source gas.

3. The method of claim 1, wherein the second reactive gas is a silicon source gas.

4. The method of claim 1, wherein the film deposited may be chosen from the group consisting of SiN, SiO₂, and SiON.

5. The method of claim 1, wherein the first reactive gas is converted to a plasma prior to contacting the wafer.

6. The method of claim 1, wherein the second reactive gas is converted to a plasma prior to contacting the wafer.

7. The method of claim 1, wherein the first reactive gas is dissociated with UV light.

8. The method of claim 1, wherein the second reactive gas is dissociated with UV light.

9. The method of claim 1, wherein the first reactive gas is dissociated with heat.

10. The method of claim 1, wherein the second reactive gas is dissociated with heat.

11. The method of claim 3, wherein the silicon source gas is selected from the group consisting of HCD, SiCl₄, SiH₂Cl₂, Sil₄, SiH₄, Si₂H₆, BTBAS, TEOS, and silicon methyl compounds.

12. The method of claim 2, wherein the N source gas is selected from the group consisting of ammonia, hydrazine, N₂, and NF₃.

13. The method of claim 2, wherein the O source gas is selected from the group consisting of oxygen, nitrous oxide, ozone, and water.

14. The method of claim 3, wherein the silicon source gas is applied at a pressure range of approximately 1 mT-325 Torr.

15. The method of claim 1, wherein the first reactive gas is applied at a pressure range of approximately 1 mT-325 Torr.

16. The method of claim 3, wherein a flow rate of the silicon source gas through the cold wall single wafer process chamber is approximately 1-1000 sccm.

17. The method of claim 1, wherein the flow rate of the first reactive gas through the cold wall single wafer process chamber is approximately 1-30,000 sccm.

18. The method of claim 1, wherein the cold wall single wafer process chamber has an interior volume of approximately 16 liters or less.

19. The method of claim 1, wherein the wafer temperature is in the range of approximately 300-750°

C.

20. The method of claim 4, wherein the wafer temperature is in the range of approximately 450-650°

C.

21. The method of claim 4, wherein the wafer temperature is approximately 500°

C.

22. The method of claim 1, wherein the first reactive gas is heated to enter the cold wall single wafer process chamber as a vapor.

23. The method of claim 1, wherein the second reactive gas is heated to enter the cold wall single wafer process chamber as a vapor.

24. The method of claim 1, further comprising placing the wafer on a susceptor and flowing an inert gas onto a bottom side of the susceptor.

25. The method of claim 1, wherein removing residual first reactive gas and residual second reactive gas is accomplished with a pump operation.

26. The method of claim 1, wherein removing residual first reactive gas and residual second reactive gas is accomplished with a purge operation.

27. The method of claim 1, wherein removing residual first reactive gas and residual second reactive gas is accomplished with a pump operation and a purge operation.

28. A method for film deposition, comprising:

flowing a first reactive gas to form a first half-layer over a top surface of a wafer in a cold wall single wafer process chamber;

stopping the flow of the first reactive gas;

removing residual first reactive gas from the cold wall single wafer process chamber;

flowing a second reactive gas to form a second half-layer over the first half-layer, where deposition of the second half-layer is non self-limiting;

controlling a thickness from the second half-layer by regulating process parameters within the cold wall single wafer process chamber;

stopping the flow of the second reactive gas;

removing residual second reactive gas from the cold wall single wafer process chamber; and

further depositing the film by CVD.

29. The method of claim 28, wherein the first reactive gas may be chosen from the group consisting of N source gas, O source gas, and N/O source gas.

30. The method of claim 28, wherein the second reactive gas may be a silicon source gas.

31. The method of claim 28, wherein the film deposited may be chosen from the group consisting of SiN, SiO₂, and SiON.

32. The method of claim 30, wherein the silicon source gas is selected from the group consisting of HCD, SiCl₄, SiH₂Cl₂, Sil₄, SiH₄, Si₂H₆, BTBAS, TEOS, and silicon methyl compounds.

33. The method of claim 29, wherein the N source gas is selected from the group consisting of ammonia, hydrazine, N₂, and NF₃.

34. The method of claim 29, wherein the O source gas is selected from the group consisting of oxygen, nitrous oxide, ozone, and water.

35. The method of claim 28, wherein the film deposited includes a barrier seed layer that is 5-150 Å

thick.

36. The method of claim 28, wherein the wafer temperature is in the range of approximately 300-750®

C.

37. The method of claim 31, wherein the wafer temperature is in the range of approximately 450-650°

C.

38. The method of claim 31, wherein the wafer temperature is approximately 500°

C.

39. A method for film deposition, comprising:

flowing a first reactive gas over a top surface of a wafer in a cold wall single wafer process chamber to deposit a first half-layer that is self-limiting;

stopping the flow of the first reactive gas;

removing residual first reactive gas from the cold wall single wafer process chamber;

flowing a second reactive gas that over the first half-layer in the cold wall single wafer process chamber to deposit a second half-layer that is self-limiting;

stopping the flow of the second reactive gas; and

removing residual second reactive gas from the cold wall single wafer process chamber.

40. The method of claim 39, wherein the first reactive gas may be chosen from the group consisting of N source gas, O source gas, and N/O source gas.

41. The method of claim 39, wherein the second reactive gas may be a silicon source gas.

42. The method of claim 39, wherein the film deposited may be chosen from the group consisting of SiN, SiO₂, and SiON.

43. The method of claim 41, wherein the silicon source gas is selected from the group consisting of HCD, SiCl₄, SiH₂Cl₂, Sil₄, BTBAS, TEOS, and silicon methyl compounds.

44. The method of claim 40, wherein the N source gas is selected from the group consisting of ammonia, hydrazine, N₂, and NF₃.

46. The method of claim 39, wherein the wafer temperature is in the range of approximately 300-750°

C.

47. The method of claim 42, wherein the wafer temperature is in the range of approximately 450-650°

C.

48. The method of claim 42, wherein the wafer temperature is approximately 500°

C.

45. The method of 40, wherein the O source gas is selected from the group consisting of oxygen, nitrous oxide, ozone, and water.

49. A method for depositing a film onto a wafer, comprising:

depositing a first SiN film having a first density;

depositing a second SiN film having a second density over the first SiN film.

50. The method of claim 49, wherein the first SiN film is deposited by CLD.

51. The method of claim 49, wherein the first SiN film is deposited by ALD.

52. The method of claim 49, wherein the second SiN film is deposited by CVD.

53. A film on a wafer, comprising:

a first Si-based film having a first density;

a second Si-based film having a second density deposited over the first film, where the first Si-based film is the same material as the second Si-based film.

54. The film of claim 53, wherein the first density is higher than the second density.

55. The film of claim 53, wherein the Si-based film deposited may be chosen from the group consisting of SiN, SiO₂, and SiON.

56. The film of claim 53, wherein the Si-based film is SiN.

57. The film of claim 56, wherein, the first density is in the range of approximately 2.97-3.00 g/cm³.

58. The film of claim 56, wherein the second density is in the range of approximately 2.85-2.96 g/cm³.

59. The film of claim 53, wherein the first Si-based film has an impurity concentration of less than 5 atom percent.

60. The film of claim 53, wherein the second Si-based film has an impurity concentration of greater than 5 atom percent.

61. The film of claim 53, wherein the first Si-based film has a relative density greater than 85%.

62. The film of claim 53, wherein the second Si-based film has a relative density in the range of approximately 50-85%.

63. A processing system, comprising:

a processing element,

a memory coupled to the processing element through a bus; and

a Si-based film deposited onto the processing element by CLD.

64. The system of claim 63, wherein the Si-based film is further deposited by MLD.

65. The system of claim 63, wherein the Si-based film deposited may be chosen from the group consisting of SiN, SiO₂, and SiON.

66. The system of claim 63, wherein a Si-based film is deposited onto the memory.