Atomic layer deposition with nitrate containing precursors

• US 6,203,613 B1
• Filed: 10/19/1999
• Issued: 03/20/2001
• Est. Priority Date: 10/19/1999
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gates, Stephen McConnell, Neumayer, Deborah Ann
• Primary Examiner(s): KUNEMUND, ROBERT M
• Application Number:
  US09/421,096
• Time in Patent Office: 518 Days
• Field of Search: 117/84, 117/104, 117/89, 117/952
• US Class Current: 117/104
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/68 Crystals with laminate structure, e.g. "superlattices"
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/02194 the material containing more than one metal element
• 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 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/3141 Deposition using atomic layer deposition techniques [ALD]
• CPC Class Codes: H01L 21/316 composed of oxides or glassy oxides or oxide based glass
• CPC Class Codes: H01L 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 21/31645 Deposition of Hafnium oxides, e.g. HfO2
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations

Abstract

Metal nitrate-containing precursor compounds are employed in atomic layer deposition processes to form metal-containing films, e.g. metal, metal oxide, and metal nitride, which films exhibit an atomically abrupt interface and an excellent uniformity.

Claims

1. A method of forming a metal-containing film on a substrate comprising an atomic layer deposition process wherein a metal nitrate-containing precursor is introduced into a reactor containing said substrate.

2. The method of claim 1 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

3. The method of claim 2 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and mixtures thereof.

4. The method of claim 1 wherein a co-reactant gas is employed with said metal nitrate-containing precursor, said co-reactant gas being introduced separately from said metal nitrate-containing precursor.

5. The method of claim 4 wherein said co-reactant gas is a reducing agent, an oxidizing agent or a nitriding agent.

6. The method of claim 5 wherein said reducing agent is selected from the group consisting of hydrogen, forming gas and combinations thereof.

7. The method of claim 5 wherein said oxidizing agent is selected from the group consisting of oxygen, ozone, water, hydrogen peroxide, nitrous oxide and combinations thereof.

8. The method of claim 5 wherein said nitriding agent is selected from the group consisting of ammonia, hydrazine, hydrogen azide, tertbutylamine, isopropylamine and combinations thereof.

9. The method of claim 1 wherein an inert gas is employed with said metal nitrate-containing precursor, said inert gas being introduced separately from said metal nitrate-containing precursor as a purge gas.

10. The method of claim 1 wherein said metal-containing precursor forms a metal nitride film, a metal oxide film, a metal film or any combination, multilayer or multicomponent thereof.

11. The method of claim 1 wherein one or more metal non-nitrate containing precursors is employed with said metal nitrate-containing precursor, each of said metal non-nitrate containing precursors being introduced separately from said metal nitrate-containing precursors.

12. The method of claim 11 wherein said metal non-nitrate containing precursor is selected from the group consisting of a metal alkyl, a metal alkoxide, a metal halide, a metal β

-diketonate, a metal hydride, a metal silyl, a metal amide and mixtures and combinations thereof.

13. A method for forming a metal oxide film on a substrate by atomic layer deposition comprising subjecting said substrate to a sequence of alternating pulses of three or more different gases to a substrate, wherein one of said gases comprising a metal nitrate-containing precursor, another of said gases is an inert gas and another of said gases is an oxidizing agent.

14. The method of claim 13 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

15. The method of claim 14 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and combinations thereof.

16. The method of claim 13 wherein said oxidizing agent is selected from the group consisting of oxygen, ozone, water, hydrogen peroxide, nitrous oxide and combinations thereof.

17. The method of claim 13 wherein two or more of said metal nitrate-containing precursors are employed.

18. A method of forming a metal film on a substrate by atomic layer deposition comprising subjecting said substrate to alternating pulses of a metal nitrate-containing precursor, a purge gas and a reducing agent.

19. The method of claim 18 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

20. The method of claim 19 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and mixtures thereof.

21. The method of claim 18 wherein said reducing agent is selected from the group consisting of hydrogen, forming gas and combinations thereof.

22. The method of claim 18 wherein two or more metal nitrate-containing precursors are employed.

23. A method of forming a metal nitride film on a substrate by atomic layer deposition said method comprising subjecting said substrate to alternating pulses of a metal nitrate-containing precursor, a purge gas and a nitriding agent.

24. The method of claim 23 herein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

25. The method of claim 24 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and mixtures thereof.

26. The method of claim 23 wherein said nitriding agent is selected from the group consisting of ammonia, hydrazine, hydrogen azide, tertbutylamine, isopropylamine and combinations thereof.

27. The method of claim 23 wherein two or more metal nitrate-containing precursors.

28. In an atomic layer deposition process for forming a metal-containing film, the improvement comprising at least a step of introducing a metal-containing precursor into a reactor containing a substrate, said metal containing precursor having the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

29. The method of claim 28 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and mixtures thereof.

30. The method of claim 28 wherein a co-reactant gas is employed with said metal nitrate-containing precursor, said co-reactant gas being introduced separately from said metal nitrate precursor.

31. The method of claim 30 wherein said co-reactant gas is a reducing agent, an oxidizing agent or a nitriding agent.

32. The method of claim 31 wherein said reducing agent is selected from the group consisting of hydrogen, forming gas and combinations thereof.

33. The method of claim 31 wherein said oxidizing agent is selected from the group consisting of oxygen, ozone, water, hydrogen peroxide, nitrous oxide and combinations thereof.

34. The method of claim 31 wherein said nitriding agent is selected from the group consisting of ammonia, hydrazine, hydrogen azide, tertbutylamine, isopropylamine and combinations thereof.

35. The method of claim 28 wherein an inert gas is employed with said metal nitrate-containing precursor, said inert gas being introduced separately from said metal nitrate-containing precursor.

36. A method for forming a multicomponent or multilayer metal oxide film on a substrate by atomic layer deposition comprising subjecting said substrate to a sequence of alternating pulses of four or more different gases, wherein one of said gases comprises a metal nitrate-containing precursor, another of said gases is an inert gas, another of said gases is an oxidizing agent and another of said gases is a metal non-nitrate containing precursor.

37. The method of claim 36 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

38. The method of claim 37 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and combinations thereof.

39. The method of claim 36 wherein said oxidizing agent is selected from the group consisting of oxygen, ozone, water, hydrogen peroxide, nitrous oxide and combinations thereof.

40. The method of claim 36 wherein two or more of said metal nitrate-containing precursors are employed.

41. The method of claim 36 wherein said metal non-nitrate containing precursor is selected from the group consisting of a metal alkyl, a metal alkoxide, a metal halide, a metal β

-diketonate, a metal hydride, a metal silyl, a metal amide and mixtures and combinations thereof.

42. A method for forming a multicomponent or multilayer metal film on a substrate by atomic layer deposition comprising subjecting said substrate to a sequence of alternating pulses of four or more different gases, wherein one of said gases comprises a metal nitrate-containing precursor, another of said gases is an inert gas, another of said gases is a reducing agent and another of said gases is a metal non-nitrate containing precursor.

43. The method of claim 42 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

44. The method of claim 43 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and combinations thereof.

45. The method of claim 42 wherein said reducing agent is selected from the group consisting of hydrogen, forming gas and combinations thereof.

46. The method of claim 42 wherein two or more of said metal nitrate-containing precursors are employed.

47. The method of claim 42 wherein said metal non-nitrate containing precursor is selected from the group consisting of a metal alkyl, a metal alkoxide, a metal halide, a metal β

-diketonate, a metal hydride, a metal silyl, a metal amide and mixtures and combinations thereof.

48. A method for forming a multicomponent or multilayer metal nitride film on a substrate by atomic layer deposition comprising subjecting said substrate to a sequence of alternating pulses of four or more different gases, wherein one of said gases comprises a metal nitrate-containing precursor, another of said gases is an inert gas, another of said gases is a nitriding agent and another of said gases is a metal non-nitrate containing precursor.

49. The method of claim 48 wherein said metal nitrate-containing precursor has the formula M(NO₃)_x wherein M is a metal selected from the group consisting of Ti, Ga, Zr, Sn, Co, V, Pt, Pd, Fe, Ni, Mo, W, Ag, Au, Hf, Cr, Cu, Mn, La, Y, Al, Gd, Nd, Sm, Si, Nb, Ta, and In;

and x is the valence of M.

50. The method of claim 49 wherein some, but not all, of said NO₃ ligands of said metal nitrate-containing precursor are replaced with a substituent R, said substituent R being selected from the group consisting of hydrogen, oxygen, oxo-nitrate, hydroxyl, aromatic, alkyl, amine, silyl, alkoxide, β

-diketone and combinations thereof.

51. The method of claim 48 wherein said nitriding agent is selected from the group consisting of ammonia, hydrazine, hydrogen azide, tertbutylamine, isopropylamine and combinations thereof.

52. The method of claim 48 wherein two or more of said metal nitrate-containing precursors are employed.

53. The method of claim 48 wherein said metal non-nitrate containing precursor is selected from the group consisting of a metal alkyl, a metal alkoxide, a metal halide, a metal β

-diketonate, a metal hydride, a metal silyl, a metal amide and mixtures and combinations thereof.