Method of forming metal oxide using an atomic layer deposition process

• US 20050277223A1
• Filed: 06/03/2005
• Published: 12/15/2005
• Est. Priority Date: 06/09/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Chon, Sang-Mun, Lee, Jung-Ho, Cho, Jun-Hyun, Choi, Jung-Sik
• Granted Patent: US 7,250,379 B2
• Time in Patent Office: Days
• US Class Current: 438/100
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• CPC Class Codes: H01L 21/02186 the material containing titanium, e.g. TiO2
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• 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 21/31604 Deposition from a gas or vapour H01L21/31691, H01L21/31695 take precedence
• CPC Class Codes: H01L 21/31608 Deposition of SiO2 H01L21/31625, H01L21/31629 and H01L21/31633 take precedence
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• CPC Class Codes: H01L 21/31637 Deposition of Tantalum oxides, e.g. Ta2O5
• CPC Class Codes: H01L 21/31641 Deposition of Zirconium oxides, e.g. ZrO2
• CPC Class Codes: H01L 21/31645 Deposition of Hafnium oxides, e.g. HfO2

Abstract

In a method of forming a metal oxide, an organic metal compound represented by the following chemical formula is introduced into a chamber to chemisorb the organic metal compound onto a substrate,
M[L1]x[L2]y where M represents a metal, L1 and L2 respectively represents a first and second ligands. In addition, x and y are independently integers and a value of (x+y) is 3 to 5. An oxygen-containing compound is introduced into the chamber to form the metal oxide. The metal oxide is formed by reacting an oxygen of the oxygen-containing compound with the metal, and separating the ligand from the metal. Thus, the metal oxide having a superior step coverage and a high dielectric constant may be formed using the organic metal compound by an atomic layer deposition process.

Claims

1. A method of forming a metal oxide comprising:

introducing an organic metal compound including a metal and at least one ligand bonded to the metal into a chamber to chemically absorb the organic metal compound onto a substrate;

removing a non-chemisorbed organic metal compound from the chamber; and

introducing an oxygen-containing compound into the chamber to form a metal oxide, the metal oxide being formed by reacting an oxygen of the oxygen-containing compound with the metal, and to separate the ligand from the metal.

2. The method of claim 1, wherein the ligand includes at least one ligand selected from the group consisting of a halide ligand, a diketonate ligand, an alkoxide ligand, an amino ligand, an alkoxyamine ligand, an amidinate ligand, and a multidentate ligand including at least two electron pair donors.

3. A method of forming a metal oxide comprising:

introducing an organic metal compound represented by the following chemical formula into a chamber to chemisorb the organic metal compound onto a substrate,

M[L1]_x[L2]_y wherein, M

represents a metal, L1 and L2 respectively represent a first and second ligands, the first and second ligands independently include at least one ligand selected from the group consisting of a halide ligand, a diketonate ligand, an alkoxide ligand, an amino ligand, an alkoxyamine ligand, an amidinate ligand, and a multidentate ligand including at least two electron pair donors, L1 and L2 are substantially different from each other, and x and y are independently integers such that a value of (x+y) is an integer ranging from 3 to 5;

removing a non-chemisorbed organic metal compound from the chamber; and

introducing an oxygen-containing compound into the chamber to form a metal oxide, the metal oxide being formed by reacting an oxygen of the oxygen-containing compound with the metal, and to separate the first and second ligands from the metal.

4. The method of claim 3, wherein the alkoxide ligand includes hydrogen or an alkyl group having about 1 to 5 carbon atoms.

5. The method of claim 3, wherein the amino ligand includes hydrogen or an alkyl group having about 1 to 5 carbon atoms.

6. The method of claim 3, wherein the metal is selected from the group consisting of hafnium (Hf), zirconium (Zr), tantalum (Ta), yttrium (Y), niobium (Nb), aluminum (Al), titanium (Ti), cerium (Ce), indium (In), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), lanthanum (La), arsenic (As), praseodymium (Pr), and antimony (Sb).

7. The method of claim 6, wherein the metal includes hafnium or titanium.

8. The method of claim 3, wherein the metal oxide is selected from the group consisting of HfO₂, ZrO₂, Ta₂O₅, Y₂O₃, Nb₂O₅, Al₂O₃, TiO₂, CeO₂, In₂O₃, SiO₂, GeO₂, SnO₂, PbO, PbO₂, Pb₃O₄, La₂O₃, As₂O₅, As₂O₃, Pr₂O₃, Sb₂O₃ and Sb₂O₅.

9. The method of claim 8, wherein the metal oxide includes HfO₂ or TiO₂.

10. The method of claim 3, wherein the oxygen-containing compound includes at least one compound selected from the group consisting of ozone (O₃), oxygen (O₂), nitrous oxide (N₂O) and water (H₂O).

11. The method of claim 10, wherein the oxygen (O₂) and the nitrous oxide (N₂O) respectively include an oxygen (O₂) plasma and a nitrous oxide (N₂O) plasma.

12. The method of claim 11, wherein the oxygen (O₂) plasma includes a remote plasma.

13. The method of claim 3, wherein the organic metal compound includes at least one compound selected from the group consisting of Hf(OtBu)₂(NEtMe)₂, Hf(OtBu)₂(NEt₂)₂, Hf(NEt₂)₂(DMAMP)₂, Hf(NEtMe)₂(DMAMP)₂, Ti(OtBu)₃Cl, Ti(OtBu)₃Me, Ti(OtBu)₂(NEt₂)₂, Ti(NEt₂)₂(DMAMP)₂, Ti(OtBu)₂(DMAMP)₂ and TiCl₂(DMAMP)₂.

14. The method of claim 3, wherein removing the non-chemisorbed organic metal compound is performed by introducing a purge gas into the chamber.

15. The method of claim 3, further comprising removing an unreacted oxygen-containing compound and the ligand separated from the metal from the chamber after forming the metal oxide.

16. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one alkoxide group and at least one amino group into a chamber to chemisorb the first reactant onto a substrate and to bond the alkoxide group and the amino group to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the amino group from the metal.

17. The method of claim 16, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal and R₁ to R₆ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

18. The method of claim 17, wherein —

R₁O and —

R₂O are substantially identical to each other.

19. The method of claim 17, wherein —

N(R₃)(R₄) and —

N(R₅)(R₆) are substantially identical to each other.

20. The method of claim 17, wherein the metal includes hafnium (Hf).

21. The method of claim 17, wherein the first reactant includes Hf(OtBu)₂(NEtMe)₂ or Hf(OtBu)₂(NEt₂)₂.

22. The method of claim 16, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

23. The method of claim 22, wherein the first reactant is introduced into the chamber with a carrier gas.

24. The method of claim 22, wherein the first reactant has a temperature of about 50°

C. to about 150°

C. before introducing into the chamber.

25. The method of claim 16, wherein removing the non-chemisorbed first reactant is carried out by introducing a purge gas into the chamber.

26. The method of claim 16, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the alkoxide group and the amino group from the chamber, the alkoxide group and the amino group being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

27. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one alkoxide group and at least one halide group into a chamber to chemisorb the first reactant onto a substrate, and to bond the alkoxide group and the halide group to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the halide group from the metal.

28. The method of claim 27, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal and R₁ to R₃ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

29. The method of claim 28, wherein the first reactant includes Ti(OtBu)₃Cl.

30. The method of claim 27, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 150°

C. to about 350°

C.

31. The method of claim 30, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

32. The method of claim 30, wherein the first reactant is introduced into the chamber with a carrier gas.

33. The method of claim 27, wherein removing the non-chemisorbed first reactant is carried out by introducing a purge gas into the chamber.

34. The method of claim 27, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the alkoxide group and the halide group from the chamber, the alkoxide group and the halide group being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

35. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one alkoxide group and at least one alkyl group into a chamber to chemisorb the first reactant onto a substrate, the alkoxide group and the alkyl group being bonded to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the alkyl group from the metal.

36. The method of claim 35, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal, and R₁ to R₃ and R independently represent a hydrogen or an alkyl group including 1 to 5 carbon atom.

37. The method of claim 36, wherein R₁ to R₃ are substantially identical to each other, and R is substantially different from the R₁ to R₃.

38. The method of claim 36, wherein the first reactant includes Ti(OtBu)₃Me.

39. The method of claim 35, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

40. The method of claim 39, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

41. The method of claim 39, wherein the first reactant is introduced into the chamber with a carrier gas.

42. The method of claim 35, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the alkoxide group and the alkyl group from the chamber, the unreacted second reactant including the second reactant that has not reacted with the chemisorbed first reactant, and the alkoxide group and the alkyl group being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

43. A method of forming a metal oxide comprising:

introducing a first reactant including a metal and at least one amino group into a chamber to chemisorb the first reactant onto a substrate, and to bond the amino group to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the amino group from the metal.

44. The method of claim 43, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal and R₁ to R₈ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

45. The method of claim 44, wherein the first reactant includes Hf(NMeiPr)₄.

46. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one amino group and at least one multidentate ligand including at least two electron pair donors into a chamber to chemisorb the first reactant onto a substrate, and to bond the amino group and the multidentate ligand to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the amino group and the multidentate ligand from the metal.

47. The method of claim 46, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal and R₁ to R₈ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

48. The method of claim 47, wherein —

N(R₁)(R₂) and —

N(R₃)(R₄) are substantially identical to each other.

49. The method of claim 47, wherein the first reactant includes at least one compound selected from the group consisting of Hf(NEt₂)₂(DMAMP)₂, Hf(NEtMe)₂(DMAMP)₂ and Ti(NEt₂)₂(DMAMP)₂.

50. The method of claim 46, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

51. The method of claim 46, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

52. The method of claim 46, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the amino group and the multidentate ligand from the chamber, the multidentate ligand being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

53. A method of forming a metal oxide comprising:

introducing a first reactant including a metal, at least one alkoxide group and at least one multidentate ligand including at least two electron pair donors into a chamber to chemisorb the first reactant onto a substrate, and to bond the alkoxide group and the multidentate ligand to the metal;

removing a non-chemisorbed first reactant from the chamber; and

introducing a second reactant into the chamber to form a metal oxide, the second reactant including an oxygen-containing compound that reacts with the metal to form the metal oxide, and to separate the alkoxide group and the multidentate ligand from the metal.

54. The method of claim 53, wherein the first reactant is represented by the following chemical formula,

wherein, M represents the metal, and R₁ to R₆ independently represent a hydrogen or an alkyl group including 1 to 5 carbon atoms.

55. The method of claim 54, wherein —

R₁O and —

R₂O are substantially identical to each other

56. The method of claim 54, wherein the first reactant includes Ti(OtBu)₂ (DMAMP)₂.

57. The method of claim 53, wherein introducing the first reactant, removing the non-chemisorbed first reactant, and introducing the second reactant are performed at a temperature of about 200°

C. to about 400°

C.

58. The method of claim 57, wherein the first reactant has a temperature of about 40°

C. to about 100°

C. before introducing into the chamber.

59. The method of claim 57, wherein after introducing the second reactant into the chamber, further comprising removing an unreacted second reactant, the alkoxide group and the multidentate ligand from the chamber, the multidentate ligand being separated from the metal by reacting the second reactant with the chemisorbed first reactant.

60. A method of forming a metal oxide comprising:

introducing an organic metal compound represented by the following chemical formula into a chamber through a first line to chemisorb the organic metal compound onto a substrate,

M[L1]_x[L2]_y

wherein, M represents a metal, L1 and L2 respectively represent a first and a second ligands, and independently includes at least one compound selected from the group consisting of a halide ligand, a diketonate ligand, an alkoxide ligand, an amino ligand, an alkoxyamine ligand, an amidinate ligand, and a multidentate ligand including at least two electron pair donors, L1 and L2 are different from each other, x and y are independently integers and a value of (x+y) is an integer of 3 to 5;

removing a non-chemisorbed first reactant from the chamber by introducing a first purge gas into the chamber through the first line;

introducing an oxygen-containing compound into the chamber through a second line to form a metal oxide, the metal oxide being formed by reacting an oxygen from the oxygen-containing compound with the metal, and separating the ligand from the metal; and

removing an unreacted oxygen-containing compound and the ligand from the chamber by introducing a second purge gas into the chamber through the second line, the unreacted oxygen-containing compound including the oxygen-containing compound that has not reacted with a chemisorbed organic metal compound, the ligand being separated from the metal.

61. The method of claim 60, wherein the metal includes hafnium (Hf) or titanium (Ti).

62. The method of claim 60, wherein the metal oxide includes hafnium oxide or titanium oxide.

63. The method of claim 60, wherein the organic metal compound includes at least one compound selected from the group consisting of Hf(OtBu)₂(NEtMe)₂, Hf(OtBu)₂(NEt₂)₂, Hf(NEt₂)₂(DMAMP)₂, Hf(NEtMe)₂(DMAMP)₂, Ti(OtBu)₃Cl, Ti(OtBu)₂Me, Ti(OtBu)₂(NEt₂)₂, Ti(NEt₂)₂(DMAMP)₂, Ti(OtBu)₂(DMAMP)₂ and TiCl₂(DMAMP)₂.

64. The method of claim 60, further comprising introducing a first reverse flow-preventing gas into the chamber through the second line while introducing the organic metal compound and removing the non-chemisorbed organic metal compound from the chamber.

65. The method of claim 64, wherein the first reverse flow-preventing gas includes an inactive gas.

66. The method of claim 60, further comprising introducing a second reverse flow-preventing gas into the chamber through the first line while introducing the oxygen-containing compound and removing the unreacted oxygen-containing compound and the ligand from the chamber.

67. The method of claim 66, wherein the second reverse flow-preventing gas includes an inactive gas.