ATOMIC LAYER DEPOSITION PROCESSES FOR RUTHENIUM MATERIALS

• US 20070054487A1
• Filed: 09/06/2006
• Published: 03/08/2007
• Est. Priority Date: 09/06/2005
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: GANGULI, SESHADRI, WU, DIEN-YEH, MA, PAUL, MARCADAL, CHRISTOPHE, SHAH, KAVITA, CHU, SCHUBERT, WU, FREDERICK
• Application Number:
  US11/470,466
• Publication Number:
  US 20070054487A1
• Time in Patent Office: Days
• US Class Current: 438/681
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45542 Plasma being used non-continuously during the ALD reactions
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations

Abstract

Embodiments of the invention provide a method for depositing ruthenium materials on a substrate by various vapor deposition processes, such as atomic layer deposition (ALD) and plasma-enhanced ALD (PE-ALD). In one aspect, the process has little or no initiation delay and maintains a fast deposition rate while forming a ruthenium material. The ruthenium material may be deposited with good step coverage, strong adhesion, and contains a low carbon concentration for high electrical conductivity. The method for depositing the ruthenium material on a substrate generally includes sequentially exposing the substrate to a pyrrolyl ruthenium precursor and a reagent during the ALD process. The pyrrolyl ruthenium precursor contains ruthenium and at least one pyrrolyl ligand. In some examples, the reagent may contain a plasma of ammonia, nitrogen, or hydrogen during a PE-ALD process. In other examples, a reducing gas may be used during a thermal ALD process.

Claims

1. A method for forming a ruthenium material on a substrate, comprising:

positioning a substrate within a process chamber; and

exposing the substrate sequentially to a reagent and a pyrrolyl ruthenium precursor to form a ruthenium material on the substrate during an atomic layer deposition process.

2. The method of claim 1, wherein the pyrrolyl ruthenium precursor comprises at least one pyrrolyl ligand with the chemical formula of:

wherein R₁, R₂, R₃, R₄, and R₅ are each independently absent or selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl, amyl, derivatives thereof, and combinations thereof.

3. The method of claim 2, wherein R₁ is absent and each R₂, R₃, R₄, or R₅ is independently hydrogen or methyl.

4. The method of claim 2, wherein R₁ is absent and each R₂ or R₅ is independently methyl or ethyl.

5. The method of claim 1, wherein the pyrrolyl ruthenium precursor comprises a first pyrrolyl ligand and a second pyrrolyl ligand.

6. The method of claim 5, wherein the first pyrrolyl ligand is different than the second pyrrolyl ligand.

7. The method of claim 5, wherein the first and second pyrrolyl ligands are the same.

8. The method of claim 1, wherein the pyrrolyl ruthenium precursor comprises a first pyrrolyl ligand and a dienyl ligand.

9. The method of claim 8, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of pentadienyl pyrrolyl ruthenium, cyclopentadienyl pyrrolyl ruthenium, alkylpentadienyl pyrrolyl ruthenium, alkylcyclopentadienyl pyrrolyl ruthenium and derivatives thereof.

10. The method of claim 1, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of alkyl pyrrolyl ruthenium, bis(pyrrolyl) ruthenium, dienyl pyrrolyl ruthenium, and derivatives thereof.

11. The method of claim 1, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of bis(tetramethylpyrrolyl) ruthenium, bis(2,5-dimethylpyrrolyl) ruthenium, bis(2,5-diethylpyrrolyl) ruthenium, bis(tetraethylpyrrolyl) ruthenium, pentadienyl tetramethylpyrrolyl ruthenium, pentadienyl 2,5-dimethylpyrrolyl ruthenium pentadienyl tetraethylpyrrolyl ruthenium, pentadienyl 2,5-diethylpyrrolyl ruthenium, 1,3-dimethylpentadienyl pyrrolyl ruthenium, 1,3-diethylpentadienyl pyrrolyl ruthenium methylcyclopentadienyl pyrrolyl ruthenium, ethylcyclopentadienyl pyrrolyl ruthenium, 2-methylpyrrolyl pyrrolyl ruthenium, 2-ethylpyrrolyl pyrrolyl ruthenium, and derivatives thereof.

12. The method of claim 1, wherein a plasma is ignited during the atomic layer deposition process.

13. The method of claim 12, wherein a plasma is generated by a radio frequency generator.

14. The method of claim 12, wherein the reagent comprises an ammonia plasma.

15. The method of claim 12, wherein the reagent comprises a nitrogen plasma.

16. The method of claim 12, wherein the reagent comprises a hydrogen plasma.

17. The method of claim 1, wherein the ruthenium material is deposited during a thermal atomic layer deposition process.

18. The method of claim 17, wherein the reagent comprises a compound selected from the group consisting of hydrogen, ammonia, hydrazine, silane, disilane, diborane, triethylborane, derivatives thereof, and combinations thereof.

19. The method of claim 18, wherein the substrate is heated to a temperature within a range from about 150°

C. to about 400°

C. during the atomic layer deposition process.

20. The method of claim 1, wherein the ruthenium material is deposited on a barrier layer disposed on the substrate and the barrier layer comprises a material selected from the group consisting of tantalum, tantalum nitride, tantalum silicon nitride, titanium, titanium nitride, titanium silicon nitride, tungsten, tungsten nitride, derivatives thereof, and combinations thereof.

21. The method of claim 1, wherein the ruthenium material is deposited on a dielectric material comprising a material selected from the group consisting of silicon dioxide, silicon nitride, silicon oxynitride, carbon-doped silicon oxides, tantalum oxide, titanium oxide, boron strontium titanate, hafnium oxide, hafnium silicate, derivatives thereof, and combinations thereof.

22. The method of claim 1, wherein a conductive metal is deposited on the ruthenium material.

23. The method of claim 22, wherein the conductive material is selected from the group consisting of copper, tungsten, aluminum, alloys thereof, and combinations thereof.

24. The method of claim 23, wherein the conductive metal comprises a seed layer and a bulk layer.

25. The method of claim 24, wherein the seed layer and the bulk layer each comprise copper.

26. The method of claim 25, wherein the seed layer is formed by an electroless deposition process, an electroplating process, or a physical vapor deposition process.

27. The method of claim 26, wherein the bulk layer is formed by an electroless deposition process, an electroplating process, or a chemical vapor deposition process.

28. The method of claim 24, wherein the seed layer and the bulk layer each comprise tungsten.

29. The method of claim 28, wherein the seed layer is formed by an atomic layer deposition process or a physical vapor deposition process.

30. The method of claim 29, wherein the bulk layer is formed by a physical vapor deposition process or a chemical vapor deposition process.

31. A method for forming a ruthenium material on a substrate, comprising:

positioning a substrate within a process chamber;

exposing the substrate to a pyrrolyl ruthenium precursor to form a ruthenium-containing layer on the substrate;

purging the process chamber with a purge gas;

exposing the substrate to a reagent to form a ruthenium material thereon; and

purging the process chamber with the purge gas.

32. The method of claim 31, wherein a plasma is ignited while exposing the substrate to the reagent.

33. The method of claim 32, wherein the reagent comprises an ammonia plasma.

34. The method of claim 32, wherein the reagent comprises a nitrogen plasma.

35. The method of claim 32, wherein the reagent comprises a hydrogen plasma.

36. The method of claim 32, wherein the pyrrolyl ruthenium precursor comprises at least one pyrrolyl ligand with the chemical formula of:

wherein R₁, R₂, R₃, R₄, and R₅ are each independently absent or selected from the group consisting of hydrogen, methyl, ethyl, propyl, butyl, amyl, derivatives thereof, and combinations thereof.

37. The method of claim 36, wherein R₁ is absent and each R₂, R₃, R₄, or R₅ is independently hydrogen or methyl.

38. The method of claim 36, wherein R₁ is absent and each R₂ or R₅ is independently methyl or ethyl.

39. The method of claim 32, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of bis(tetramethylpyrrolyl) ruthenium, bis(2,5-dimethylpyrrolyl) ruthenium, bis(2,5-diethylpyrrolyl) ruthenium, bis(tetraethylpyrrolyl) ruthenium pentadienyl tetramethylpyrrolyl ruthenium, pentadienyl 2,5-dimethylpyrrolyl ruthenium, pentadienyl tetraethylpyrrolyl ruthenium, pentadienyl 2,5-diethylpyrrolyl ruthenium, 1,3-dimethylpentadienyl pyrrolyl ruthenium, 1,3-diethylpentadienyl pyrrolyl ruthenium, methylcyclopentadienyl pyrrolyl ruthenium, ethylcyclopentadienyl pyrrolyl ruthenium, 2-methylpyrrolyl pyrrolyl ruthenium, 2-ethylpyrrolyl pyrrolyl ruthenium, derivatives thereof, and combinations thereof.

40. The method of claim 31, wherein the ruthenium material is deposited during a thermal atomic layer deposition process.

41. The method of claim 40, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of bis(tetramethylpyrrolyl) ruthenium, bis(2,5-dimethylpyrrolyl) ruthenium, bis(2,5-diethylpyrrolyl) ruthenium, bis(tetraethylpyrrolyl) ruthenium pentadienyl tetramethylpyrrolyl ruthenium, pentadienyl 2,5-dimethylpyrrolyl ruthenium, pentadienyl tetraethylpyrrolyl ruthenium, pentadienyl 2,5-diethylpyrrolyl ruthenium, 1,3-dimethylpentadienyl pyrrolyl ruthenium, 1,3-diethylpentadienyl pyrrolyl ruthenium, methylcyclopentadienyl pyrrolyl ruthenium, ethylcyclopentadienyl pyrrolyl ruthenium, 2-methylpyrrolyl pyrrolyl ruthenium, 2-ethylpyrrolyl pyrrolyl ruthenium, derivatives thereof, and combinations thereof.

42. The method of claim 41, wherein the reagent comprises a compound selected from the group consisting of hydrogen, ammonia, hydrazine, silane, disilane, diborane, trimethylborane, triethylborane, derivatives thereof, and combinations thereof.

43. A method for forming a ruthenium material on a substrate, comprising:

positioning a substrate containing a dielectric material within a process chamber; and

exposing the substrate sequentially to a reagent and a pyrrolyl ruthenium precursor to form a ruthenium material on the dielectric material during an atomic layer deposition process.

44. The method of claim 43, wherein the dielectric material comprises a material selected from the group consisting of silicon dioxide, silicon nitride, silicon oxynitride, carbon-doped silicon oxides, tantalum oxide, titanium oxide, boron strontium titanate, hafnium oxide, hafnium silicate, derivatives thereof, and combinations thereof.

45. A method for forming a ruthenium material on a substrate, comprising:

positioning a substrate within a process chamber; and

exposing the substrate sequentially to a reagent and a pyrrolyl ruthenium precursor to form a ruthenium material on the substrate during an atomic layer deposition process, wherein the pyrrolyl ruthenium precursor is selected from the group consisting of bis(tetramethylpyrrolyl) ruthenium, bis(2,5-dimethylpyrrolyl) ruthenium, bis(2,5-diethylpyrrolyl) ruthenium, bis(tetraethylpyrrolyl) ruthenium, pentadienyl tetramethylpyrrolyl ruthenium, pentadienyl 2,5-dimethylpyrrolyl ruthenium, pentadienyl tetraethylpyrrolyl ruthenium, pentadienyl 2,5-diethylpyrrolyl ruthenium, 1,3-dimethylpentadienyl pyrrolyl ruthenium, 1,3-diethylpentadienyl pyrrolyl ruthenium, methylcyclopentadienyl pyrrolyl ruthenium, ethylcyclopentadienyl pyrrolyl ruthenium, 2-methylpyrrolyl pyrrolyl ruthenium, 2-ethylpyrrolyl pyrrolyl ruthenium, derivatives thereof, and combinations thereof.