Electroless deposition process on a silicide contact

• US 20060246217A1
• Filed: 03/20/2006
• Published: 11/02/2006
• Est. Priority Date: 03/18/2005
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Weidman, Timothy W., Shanmugasundram, Arulkumar, Stewart, Michael P., Gandikota, Srinivas, Zhu, Zhize, Gelatos, Avgerinos V.
• Application Number:
  US11/385,047
• Publication Number:
  US 20060246217A1
• Time in Patent Office: Days
• US Class Current: 427/99.500
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C23C 18/1651 Two or more layers only obtained by electroless plating
• CPC Class Codes: C23C 18/1893 with use of organic or inorganic compounds other than metals, first
• CPC Class Codes: C23C 18/32 Coating with nickel, cobalt or mixtures thereof with phosphorus or boron C23C18/50 takes precedence
• CPC Class Codes: C23C 18/34 using reducing agents
• CPC Class Codes: H01L 21/02063 the processing being the formation of vias or contact holes
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• CPC Class Codes: H01L 21/288 from a liquid, e.g. electrolytic deposition
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76814 post-treatment or after-treatment, e.g. cleaning or removal of oxides on underlying conductors
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76847 the layer being positioned within the main fill metal
• CPC Class Codes: H01L 21/76855 After-treatment introducing at least one additional element into the layer
• CPC Class Codes: H01L 21/76856 by treatment in plasmas or gaseous environments, e.g. nitriding a refractory metal liner
• CPC Class Codes: H01L 21/76867 characterized by methods of formation other than PVD, CVD or deposition from a liquids PVD H01L21/2855; CVD H01L21/28556; deposition from liquids H01L21/288
• CPC Class Codes: H01L 21/76874 for electroless plating
• CPC Class Codes: H01L 21/76879 by selective deposition of conductive material in the vias, e.g. selective C.V.D. on semiconductor material, plating plating on semiconductors in general H01L21/288
• CPC Class Codes: H01L 21/76889 by forming silicides of refractory metals

Abstract

Embodiments as described herein provide methods for depositing a material on a substrate during electroless deposition processes, as well as compositions of the electroless deposition solutions. In one embodiment, the substrate contains a contact aperture having an exposed silicon contact surface. In another embodiment, the substrate contains a contact aperture having an exposed silicide contact surface. The apertures are filled with a metal contact material by exposing the substrate to an electroless deposition process. The metal contact material may contain a cobalt material, a nickel material, or alloys thereof. Prior to filling the apertures, the substrate may be exposed to a variety of pretreatment processes, such as preclean processes and activations processes. A preclean process may remove organic residues, native oxides, and other contaminants during a wet clean process or a plasma etch process. Embodiments of the process also provide the deposition of additional layers, such as a capping layer.

Claims

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

positioning a substrate within a process chamber, wherein the substrate comprises an aperture containing an exposed silicide contact surface;

exposing the exposed silicide contact surface to a deposition solution to form a metal contact material over the exposed silicide contact surface during an electroless deposition process; and

filling the aperture with the metal contact material by continuing the electroless deposition process.

2. The method of claim 1, wherein the exposed silicide contact surface comprises at least one metal selected from the group consisting of cobalt, nickel, tungsten, molybdenum, rhenium, titanium, tantalum, hafnium, zirconium, alloys thereof, and combinations thereof.

3. The method of claim 2, wherein the metal contact material comprises a material selected from the group consisting of nickel, nickel phosphide, nickel boride, cobalt, cobalt tungsten, cobalt tungsten phosphide, cobalt tungsten boride, cobalt tungsten phosphide boride, cobalt nickel, cobalt phosphide, cobalt boride, cobalt nickel phosphide, cobalt nickel boride, derivatives thereof, alloys thereof, and combinations thereof.

4. The method of claim 1, wherein a capping layer is deposited on the exposed silicide contact surface prior to filling the aperture with the metal contact material.

5. The method of claim 4, wherein the capping layer comprises a material selected from the group consisting of cobalt tungsten phosphide, cobalt tungsten boride, cobalt tungsten phosphide boride, derivatives thereof, alloys thereof, and combinations thereof.

6. The method of claim 5, wherein the capping layer is deposited during an electroless deposition process.

7. The method of claim 1, wherein the exposed silicide contact surface is exposed to a preclean process prior to depositing the metal contact material thereon.

8. The method of claim 7, wherein the substrate is exposed to a plasma to remove native oxides or contaminants from the exposed suicide contact surface during the preclean process.

9. The method of claim 8, wherein a thin film is formed on the substrate by the plasma and the thin film is removed by a vacuum sublimation process.

10. The method of claim 8, further comprising exposing the substrate to the plasma and a process gas comprising a gas mixture of ammonia and nitrogen trifluoride.

11. The method of claim 10, wherein the gas mixture has a molar ratio of the ammonia to the nitrogen trifluoride within a range from about 1:

1 to about 30;

1.

12. The method of claim 7, wherein the preclean process is a wet clean process.

13. The method of claim 12, wherein the wet clean process comprises exposing the substrate to a wet clean solution comprising hydrogen fluoride and a basic compound selected from the group consisting of ammonium hydroxide, tetramethylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, derivatives thereof, salts thereof, and combinations thereof.

14. The method of claim 13, wherein the wet clean solution comprises an EA-HF complex, a DEA-HF complex, a TEA-HF complex, a DEA-EA-HF complex, a DEA-TEA-HF complex, a TEA-EA-HF complex, derivatives thereof, salts thereof, and combinations thereof.

15. The method of claim 12, wherein the wet clean process comprises exposing the substrate to a wet clean solution comprising hydrogen peroxide and a basic compound selected from the group consisting of ammonium hydroxide, tetramethylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, derivatives thereof, salts thereof, and combinations thereof.

16. The method of claim 12, wherein the wet clean process comprises exposing the substrate to a wet clean solution comprising hydrogen peroxide and hydrogen chloride.

17. A method for depositing a material on a substrate, comprising:

positioning a substrate within a process chamber, wherein the substrate comprises an aperture containing an exposed silicon contact surface;

forming a metal silicide layer on the exposed silicon contact surface; and

exposing the substrate to an electroless deposition process to fill the aperture with a metal contact material.

18. The method of claim 17, wherein the metal silicide layer comprises at least one metal selected from the group consisting of cobalt, nickel, tungsten, molybdenum, rhenium, titanium, tantalum, hafnium, zirconium, alloys thereof, and combinations thereof.

19. The method of claim 17, wherein the metal contact material comprises a material selected from the group consisting of nickel, nickel phosphide, nickel boride, cobalt, cobalt tungsten, cobalt tungsten phosphide, cobalt tungsten boride, cobalt tungsten phosphide boride, cobalt nickel, cobalt phosphide, cobalt boride, cobalt nickel phosphide, cobalt nickel boride, derivatives thereof, alloys thereof, and combinations thereof.

20. The method of claim 19, wherein the electroless deposition process comprises sequentially exposing the substrate to a first electroless solution containing a cobalt source and to a second electroless solution containing a nickel source.

21. The method of claim 20, wherein the substrate is rinsed after each exposure of the first electroless solution and the second electroless solution.

22. The method of claim 21, wherein a process cycle of the sequential exposures of the first and second electroless solutions is repeated to form the metal contact material as a cobalt-nickel stack material having a predetermined thickness.

23. The method of claim 17, wherein a capping layer is deposited on the metal silicide layer prior to filling the aperture with the metal contact material.

24. The method of claim 23, wherein the capping layer comprises a material selected from the group consisting of cobalt tungsten phosphide, cobalt tungsten boride, cobalt tungsten phosphide boride, derivatives thereof, alloys thereof, and combinations thereof.

25. The method of claim 24, wherein the capping layer is deposited during an electroless deposition process.

26. The method of claim 17, wherein a self assembled monolayer is deposited within the aperture prior to forming the metal contact material.

27. The method of claim 17, wherein the metal silicide layer is formed from the exposed silicon contact surface by exposing the substrate to a metal-containing activation solution.

28. The method of claim 27, wherein the metal-containing activation solution comprises a cobalt source, a fluoride source, and a hypophosphite source.

29. The method of claim 17, wherein the metal silicide layer is exposed to a preclean process prior to depositing the metal contact material thereon.

30. The method of claim 29, wherein the substrate is exposed to a plasma to remove native oxides or contaminants from the metal silicide layer during the preclean process.

31. The method of claim 30, wherein a thin film is formed on the substrate by the plasma and the thin film is removed by a vacuum sublimation process.

32. The method of claim 30, further comprising exposing the substrate to the plasma and a process gas comprising a gas mixture of ammonia and nitrogen trifluoride.

33. The method of claim 29, wherein the preclean process is a wet clean process that provides exposing the substrate to a wet clean solution comprising hydrogen fluoride and a basic compound selected from the group consisting of ammonium hydroxide, tetramethylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, derivatives thereof, salts thereof, and combinations thereof.

34. The method of claim 33, wherein the wet clean solution comprises an EA-HF complex, a DEA-HF complex, a TEA-HF complex, a DEA-EA-HF complex, a DEA-TEA-HF complex, a TEA-EA-HF complex, derivatives thereof, salts thereof, and combinations thereof.

35. The method of claim 29, wherein the preclean process is a wet clean process that provides exposing the substrate to a wet clean solution comprising hydrogen peroxide and a basic compound selected from the group consisting of ammonium hydroxide, tetramethylammonium hydroxide, ethanolamine, diethanolamine, triethanolamine, derivatives thereof, salts thereof, and combinations thereof.

36. A method for depositing a material on a substrate, comprising:

positioning a substrate within a process chamber, wherein the substrate comprises an aperture containing an exposed silicide contact surface; and

filling the aperture with a cobalt-nickel stack material during an electroless deposition process comprising sequentially exposing the substrate to a first electroless solution containing a cobalt source and to a second electroless solution containing a nickel source.

37. The method of claim 36, wherein the cobalt-nickel stack material comprises a first layer comprising a material selected from the group consisting of cobalt, cobalt phosphide, cobalt boride, cobalt tungsten, cobalt tungsten phosphide, cobalt tungsten boride, cobalt tungsten phosphide boride, derivatives thereof, alloys thereof, and combinations thereof, and a second layer comprising a material selected from the group consisting of nickel, nickel phosphide, nickel boride, derivatives thereof, alloys thereof, and combinations thereof.

38. A composition of a cobalt deposition solution, comprising:

a cobalt source at a concentration within a range from about 1 mM to about 150 mM;

a reducing agent source at a concentration within a range from about 1 mM to about 100 mM; and

a chelating agent source at a concentration within a range from about 10 mM to about 500 mM.

39. The composition of claim 38, further comprising:

the cobalt source at a concentration within a range from about 10 mM to about 100 mM;

the reducing agent source at a concentration within a range from about 5 mM to about 50 mM; and

the chelating agent source at a concentration within a range from about 50 mM to about 300 mM.

40. The composition of claim 39, further comprising:

the cobalt source at a concentration within a range from about 20 mM to about 80 mM;

the reducing agent source at a concentration within a range from about 10 mM to about 40 mM; and

the chelating agent source at a concentration within a range from about 75 mM to about 250 mM.

41. The composition of claim 40, further comprising the cobalt source at a concentration of about 35 mM, the reducing agent source at a concentration of about 25 mM, and the chelating agent source at a concentration of about 150 mM.

42. The composition of claim 38, wherein the chelating agent source is selected from the group consisting of citric acid, lactic acid, glycine, ethanolamine, diethanolamine, triethanolamine, salts thereof, derivatives thereof, and combinations thereof.

43. The composition of claim 42, wherein the reducing agent source comprises dimethylamine-borane complex.

44. The composition of claim 43, further comprising boric acid.

45. The composition of claim 38, further comprising saccharin.

46. The composition of claim 38, further comprising ammonium fluoride or tetramethylammonium fluoride.

47. The composition of claim 38, further comprising a pH value within a range from about 8 to about 10.

48. The composition of claim 47, wherein the pH value is about 9.2.

50. The composition of claim 48, further comprising:

the nickel source at a concentration within a range from about 5 mM to about 100 mM;

the reducing agent source at a concentration within a range from about 5 mM to about 100 mM; and

the chelating agent source at a concentration within a range from about 50 mM to about 300 mM.

51. The composition of claim 50, further comprising:

the nickel source at a concentration within a range from about 10 mM to about 80 mM;

the reducing agent source at a concentration within a range from about 10 mM to about 80 mM; and

the chelating agent source at a concentration within a range from about 75 mM to about 200 mM.

52. The composition of claim 51, further comprising the nickel source at a concentration of about 40 mM, the reducing agent source at a concentration of about 40 mM, and the chelating agent source at a concentration of about 150 mM.

49. A composition of a nickel deposition solution, comprising:

a nickel source at a concentration within a range from about 1 mM to about 150 mM;

a reducing agent source at a concentration within a range from about 1 mM to about 150 mM; and

a chelating agent source at a concentration within a range from about 10 mM to about 500 mM.

53. The composition of claim 49, wherein the chelating agent source is selected from the group consisting of citric acid, lactic acid, glycine, ethanolamine, diethanolamine, triethanolamine, salts thereof, derivatives thereof, and combinations thereof.

54. The composition of claim 53, wherein the reducing agent source comprises dimethylamine-borane complex.

55. The composition of claim 54, further comprising boric acid.

56. The composition of claim 49, further comprising a pH value within a range from about 8 to about 10.

57. The composition of claim 56, wherein the pH value is about 9.2.