Apparatus and method to achieve continuous interface and ultrathin film during atomic layer deposition

• US 20030027431A1
• Filed: 09/27/2002
• Published: 02/06/2003
• Est. Priority Date: 12/22/1999
• Status: Active Grant

• Current Assignee: Eugenus, Inc.
• Original Assignee: Carl Galewski, Ofer Sneh, Thomas E. Seidel
• Inventors: Sneh, Ofer, Galewski, Carl, Seidel, Thomas E.
• Granted Patent: US 6,638,859 B2
• Time in Patent Office: Days
• US Class Current: 438/758
• CPC Class Codes: C23C 16/02 Pretreatment of the material to be coated C23C16/04 takes precedence
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/45536 Use of plasma, radiation or electromagnetic fields
• CPC Class Codes: C23C 16/45544 characterized by the apparatus

Abstract

A method and apparatus for performing atomic layer deposition in which a surface of a substrate is pretreated to make the surface of the substrate reactive for performing atomic layer deposition.

Claims

1. A method of performing atomic layer deposition comprising:

pretreating a surface of a substrate to make the surface of the substrate reactive for performing atomic layer deposition;

introducing a first precursor to deposit a first reactive species on the surface of the substrate, the pretreated surface being more receptive to having chemical termination sites for depositing the first reactive species, due to said pretreating the surface; and

introducing a second precursor to have a second reactive species react with the deposited first reactive species.

2. The method of claim 1 further including forming a uniform film layer of 50 angstroms or less in thickness.

3. The method of claim 1 wherein said pretreating is performed by a plasma process.

4. The method of claim 1 wherein said pretreating the surface includes introducing a radical species to attach to the surface of the substrate to increase termination sites for the first reactive species.

5. The method of claim 4 wherein said pretreating is performed by a plasma process.

6. The method of claim 1 wherein said pretreating the surface includes introducing a radical species to exchange bonds at the surface of the substrate to increase termination sites for the first reactive species.

7. The method of claim 6 wherein said pretreating is performed by a plasma process.

8. The method of claim 1 wherein said pretreating the surface includes depositing an intermediate layer on the substrate prior to introducing the first precursor, in which the intermediate layer provides more termination sites for the first reactive species than the substrate or where the substrate cannot be made reactive to atomic layer deposition.

9. The method of claim 8 wherein said pretreating is performed by a plasma process.

10. The method of claim 8 wherein said pretreating is performed by an atomic layer deposition plasma process.

11. The method of claim 1 wherein said pretreating the surface includes introducing a radical species to leach molecules from the substrate to increase termination sites for the first reactive species.

12. The method of claim 11 wherein said pretreating is performed by a plasma process.

13. The method of claim 1 wherein Al₂O₃ is deposited on silicon by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O/NH₃ plasma to form a layer of silicon oxide or silicon oxinitride, in which OH or NH_x group forms the chemical termination sites on silicon.

14. The method of claim 1 wherein Al₂O₃ is deposited on silicon by atomic layer deposition in which said pretreating includes forming a layer of SiO₂ that is hydroxilated by exposing HF cleaned silicon to a pulse of H₂O to form the chemical termination sites on silicon.

15. The method of claim 1 wherein Al₂O₃ is deposited on WN_x by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to leach fluorine from WN_x to form NH_x as the chemical termination sites on WN_x.

16. The method of claim 1 wherein Al₂O₃ is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x as the chemical termination sites on TiN.

17. The method of claim 1 wherein Al₂O₃ is deposited on Ti by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the chemical termination sites on Ti.

18. The method of claim 1 wherein Al₂O₃ is deposited on W by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the chemical termination sites on W.

19. The method of claim 1 wherein Al₂O₃ is deposited on Ta by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the chemical termination sites on Ta.

20. The method of claim 1 wherein Al₂O₃ is deposited on Ta_xN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x as the chemical termination sites on Ta_xN.

21. The method of claim 1 wherein Ta₂O₅ is deposited on Al₂O₃ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species as the chemical termination sites on Al₂O₃.

22. The method of claim 1 wherein Al₂O₃ is deposited on Ta₂O₅ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species as the chemical termination sites on Ta₂O₅.

23. The method of claim 1 wherein TiO_x is deposited on Al₂O₃ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species as the chemical termination sites on Al₂O₃

24. The method of claim 1 wherein Al₂O₃ is deposited on TiO_x by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species as the chemical termination sites on TiO_x.

25. The method of claim 1 wherein TiO_x is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x species as the chemical termination sites on TiN.

26. The method of claim 1 wherein W is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x species as the chemical termination sites on TiN.

27. The method of claim 1 wherein WN_x is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x species as the chemical termination sites on TiN.

28. The method of claim 1 wherein WN_x is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species that are reactive with TiCl₄ and in which the TiCl₄ is used to grow an intermediate layer of Ti or TiN to form NH_x as the chemical termination sites on Ti or TiN.

29. The method of claim 1 wherein W is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species that are reactive with TiCl₄ and in which the TiCl₄ is used to grow an intermediate layer of Ti or TiN to form NH_x as the chemical termination sites on Ti or TiN.

30. The method of claim 1 wherein W is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH species that are reactive with TaCl₅ and in which the TaCl₅ is used to grow an intermediate layer of Ta_xN to form NH_x as the chemical termination sites on Ta_xN.

31. The method of claim 1 wherein WN_x is deposited on hydrocarbon polymer by atomic layer deposition in which said pretreating includes introducing NF₃ plasma to generate fluorine atoms that leach hydrogen from the hydrocarbon polymer and in which the leached surface is reacted with TiCl₄ to grow an intermediate layer of TiN or a combination of Ti/TiN to form NH_x as the chemical termination sites on TiN or Ti/TiN.

32. The method of claim 1 wherein WN_x is deposited on perfluorocarbon polymer by atomic layer deposition in which said pretreating includes introducing H₂/NH₃ plasma to generate hydrogen atoms and NH_x radicals that leach fluorine from the hydrocarbon polymer and in which the leached surface is reacted with TiCl₄ to grow an intermediate layer of TiN or a combination of Ti/TiN to form NH_x as the chemical termination sites on TiN or Ti/TiN.

33. The method of claim 1 wherein a second oxide is deposited on a first oxide by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to activate the first oxide and to terminate the surface with OH species that are reactive with a metal precursor for the second oxide layer.

34. The method of claim 1 wherein an oxide is deposited on metal, semiconductor or metal nitride by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to terminate the surface with NH_x species that are reactive with a metal precursor.

35. The method of claim 1 wherein a metal, semiconductor or conductive metalnitride is deposited on oxide by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma which is used to terminate the surface with NH_x species.

36. The method of claim 1 wherein a metal, semiconductor or conductive metalnitride is deposited on oxide by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma generated radicals which are used to terminate the surface with OH species.

37. An apparatus for performing atomic layer deposition comprising:

a processing chamber for subjecting a substrate to atomic layer deposition to deposit a film layer;

a mixing manifold for mixing chemicals with a carrier gas, said mixing manifold coupled to said processing chamber for delivery of a first precursor chemical during a first time period and delivery of a second precursor chemical during a second period to generate a first and second plasma, respectively, to perform atomic layer deposition to deposit the film layer;

said mixing manifold also coupled to receive a pretreating chemical specie for coupling into said processing chamber prior to introduction of the first and second precursor chemicals, said pretreating chemical specie introduced into said processing chamber to pretreat the substrate surface to make its surface more reactive to the first precursor chemical.

38. The apparatus of claim 37 wherein said pretreating chemical specie introduces a radical species to attach to the surface of the substrate to increase termination sites for the first precursor chemical.

39. The apparatus of claim 37 wherein said pretreating chemical specie introduces a radical species to exchange bonds at the surface of the substrate to increase termination sites for the first precursor chemical.

40. The apparatus of claim 37 wherein said pretreating chemical specie deposits an intermediate layer on the substrate prior to introducing the first precursor chemical, in which the intermediate layer provides more termination sites for the first precursor chemical or where the substrate cannot be made reactive to atomic layer deposition.

41. The apparatus of claim 37 wherein said pretreating chemical specie introduces a radical species to leach molecules from the substrate to increase termination sites for the first precursor chemical.

42. A method to perform atomic layer deposition comprising:

pretreating a surface of a substrate or a material layer formed on the substrate by introducing a radical specie including any combination of O₂, H₂, H₂O, NH₃, NF₃, N₂, Cl and F to increase AH_x termination sites on the surface, where x is an integer and A is a non-metal capable of bonding with hydrogen H;

introducing a first precursor to deposit a first reactive specie on the surface, the surface when pretreated being more receptive to have additional bonding with the first reactive specie, due to the increase of AH_x termination sites on the surface; and

introducing a second precursor, after the bonding of the first reactive specie, to deposit a second reactive specie to react with the deposited first reactive specie to form a film layer.

43. The method of claim 42 further including forming the film layer to have a thickness of 50 angstroms or less by repeatedly introducing the first precursor followed by the second precursor.

44. The method of claim 42 wherein said pretreating the surface includes introducing the radical specie to exchange bonds at the surface of the substrate to increase AH_x termination sites for the first reactive specie.

45. The method of claim 42 wherein said pretreating the surface forms NH_x termination sites.

46. The method of claim 42 further comprising forming an intermediate layer on the substrate prior to introducing the first precursor, wherein the radical specie is introduced with the intermediate layer to increase termination sites for the first reactive specie.

47. The method of claim 42 wherein said pretreating the surface includes introducing the radical specie to leach molecules from the substrate to increase termination sites for the first reactive specie.

48. The method of claim 42 wherein said pretreating further includes introducing the radical specie by plasma.

49. The method of claim 42 wherein said pretreating further includes introducing the radical specie by plasma and the reactive species form the film layer, wherein the film layer is comprised of a metal, metal oxide or metal nitride.

50. The method of claim 48 wherein Al₂O₃ is deposited on silicon by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O/NH₃ plasma to form a film layer of silicon oxide or silicon oxinitride, in which OH or NH_x group forms the termination sites on silicon.

51. The method of claim 48 wherein Al₂O₃ is deposited on WN_y, where y is an integer, by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to leach fluorine from WN_y to form NH_x as the termination sites on WN_y.

52. The method of claim 48 wherein Al₂O₃ is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x as the termination sites on TiN.

53. The method of claim 48 wherein Al₂O₃ is deposited on Ti by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the termination sites on Ti.

54. The method of claim 48 wherein Al₂O₃ is deposited on W by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the termination sites on W.

55. The method of claim 48 wherein Al₂O₃ is deposited on Ta by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to nitridize the surface to form NH_x as the termination sites on Ta.

56. The method of claim 48 wherein Al₂O₃ is deposited on Ta_yN, where y is an integer, by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x as the termination sites on Ta_yN.

57. The method of claim 48 wherein Ta₂O₅ is deposited on Al₂O₃ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie as the termination sites on Al₂O₃.

58. The method of claim 48 wherein Al₂O₃ is deposited on Ta₂O₅ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie as the termination sites on Ta₂O₅.

59. The method of claim 48 wherein TiO_z, where z is an integer, is deposited on Al₂O₃ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie as the termination sites on Al₂O₃

60. The method of claim 48 wherein Al₂O₃ is deposited on TiO_z, where z is an integer, by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie as the termination sites on TiO_z.

61. The method of claim 48 wherein TiO_z, where z is an integer, is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x specie as the termination sites on TiN.

62. The method of claim 48 wherein W is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x specie as the termination sites on TiN.

63. The method of claim 48 wherein WN_y, where y is an integer, is deposited on TiN by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to form NH_x specie as the termination sites on TiN.

64. The method of claim 48 wherein WN_y, where y is an integer, is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie that are reactive with TiCl₄ and in which the TiCl₄ is used to grow an intermediate layer of Ti or TiN to form NH, as the termination sites on Ti or TiN.

65. The method of claim 48 wherein W is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie that are reactive with TiCl₄ and in which the TiCl₄ is used to grow an intermediate layer of Ti or TiN to form NH_x as the termination sites on Ti or TiN.

66. The method of claim 48 wherein W is deposited on SiO₂ by atomic layer deposition in which said pretreating includes introducing O₂/H₂/H₂O plasma to form OH specie that is reactive with TaCl₅ and in which the TaCl₅ is used to grow an intermediate layer of Ta_zN, where z is an integer, to form NH_x as the termination sites on Ta_zN.

67. The method of claim 48 wherein WN_y, where y is an integer, is deposited on hydrocarbon polymer by atomic layer deposition in which said pretreating includes introducing NF₃ plasma to generate fluorine atoms that leach hydrogen from the hydrocarbon polymer and in which the leached surface is reacted with TiCl₄ to grow an intermediate layer of TiN or a combination of Ti/TiN to form NH_x as the termination sites on TiN or Ti/TiN.

68. The method of claim 48 wherein WN_y, where y is an integer, is deposited on perfluorocarbon polymer by atomic layer deposition in which said pretreating includes introducing H₂/NH₃ plasma to generate hydrogen atoms and NH_x radicals that leach fluorine from the hydrocarbon polymer and in which the leached surface is reacted with TiCl₄ to grow an intermediate layer of TiN or a combination of Ti/TiN to form NH_x as the termination sites on TiN or Ti/TiN.

69. The method of claim 48 wherein an oxide is deposited on metal, semiconductor or metal nitride by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma to terminate the surface with NH_x specie that are reactive with a metal precursor.

70. The method of claim 48 wherein a metal, semiconductor or conductive metal nitride is deposited as the film layer on oxide by atomic layer deposition in which said pretreating includes introducing NH₃/H₂/N₂ plasma which is used to terminate the surface with NH_x specie.

71. A method to perform atomic layer deposition comprising:

depositing an intermediate layer;

pretreating a surface of the deposited intermediate layer by introducing a radical specie including any combination of O₂, H₂, H₂O, NH₃, NF₃, N₂, Cl and F to increase AH_x termination sites on the surface, where x is an integer and A is a non-metal capable of bonding with hydrogen H;

introducing a first precursor to deposit a first reactive specie on the surface, the surface when pretreated being more receptive to have additional bonding with the first reactive specie, due to the increase of AH_x termination sites on the surface; and

introducing a second precursor, after the bonding of the first reactive specie, to deposit a second reactive specie to react with the deposited first reactive specie to form a film layer.

72. A method to perform atomic layer deposition comprising:

leaching hydrogen or fluorine from a surface by pretreating the surface by introducing a radical specie including any combination of O₂, H₂, H₂O, NH₃, NF₃, N₂, Cl and F to increase AH_x termination sites on the surface, where x is an integer and A is a non-metal capable of bonding with hydrogen H;

introducing a first precursor to deposit a first reactive specie on the surface, the surface when pretreated being more receptive to have additional bonding with the first reactive specie, due to the increase of AH_x termination sites on the surface; and

introducing a second precursor, after the bonding of the first reactive specie, to deposit a second reactive specie to react with the deposited first reactive specie to form a film layer.

73. A structure formed on a substrate comprising:

a material layer formed on the substrate in which the material layer is pretreated by introducing a radical specie including any combination of O₂, H₂, H₂O, NH₃, NF₃, N₂, Cl and F to increase AH_x termination sites on the surface of the material layer, where x is an integer and A is a non-metal capable of bonding with hydrogen H;

a film layer formed above said material layer by repeated introduction of a first precursor followed by a second precursor to deposit said film layer by atomic layer deposition, the first precursor to deposit a first reactive specie on the surface of the material layer, the surface when pretreated being more receptive to have additional bonding with the first reactive specie, due to the increase of AH_x termination sites on the surface and the second precursor to deposit a second reactive specie to react with the deposited first reactive specie to form said film layer.