Apparatus, precursors and deposition methods for silicon-containing materials

• US 7,425,350 B2
• Filed: 04/29/2005
• Issued: 09/16/2008
• Est. Priority Date: 04/29/2005
• Status: Active Grant

• Current Assignee: ASM Japan K.K. (ASM International NV)
• Original Assignee: ASM Japan K.K. (ASM International NV)
• Inventors: Todd, Michael A.
• Primary Examiner(s): Zimmer; Marc S.
• Application Number:
  US11/117,988
• Publication Number:
  US 20060247404A1
• Time in Patent Office: 1,236 Days
• Field of Search: None
• US Class Current: 427/372.2
• CPC Class Codes: C08G 77/04 Polysiloxanes
• CPC Class Codes: C09D 183/04 Polysiloxanes
• CPC Class Codes: C09D 4/00 Coating compositions, e.g. paints, varnishes or lacquers, based on organic non-macromolecular compounds having at least one polymerisable carbon-to-carbon unsaturated bond ; Coating compositions, based on monomers of macromolecular compounds of groups C09D183/00 - C09D183/16
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249969 Of silicon-containing material [e.g., glass, etc.]

Abstract

A method for making a Si-containing material comprises transporting a pyrolyzed Si-precursor to a substrate and polymerizing the pyrolyzed Si-precursor on the substrate to form a Si-containing film. Polymerization of the pyrolyzed Si-precursor may be carried out in the presence of a porogen to thereby form a porogen-containing Si-containing film. The porogen may be removed from the porogen-containing Si-containing film to thereby form a porous Si-containing film. Preferred porous Si-containing films have low dielectric constants and thus are suitable for various low-k applications such as in microelectronics and microelectromechanical systems.

Claims

1. A method for forming a film, comprising:

pyrolyzing a vaporized Si precursor in a first zone to thereby form an activated Si-containing intermediate;

transporting the activated Si-containing intermediate to a second zone;

polymerizing the activated Si-containing intermediate in the second zone to thereby form a Si-containing film; and

forming at least one volatile by-product;

the Si precursor being selected from the group consisting of

2. The method of claim 1 in which the volatile by-product comprises a compound selected from the group consisting of BrC(CH₃)₃ and ClC(CH₃)₃.

3. A method for forming a film, comprising:

pyrolyzing a vaporized Si precursor in a first zone to thereby form an activated Si-containing intermediate;

transporting the activated Si-containing intermediate to a second zone; and

polymerizing the activated Si-containing intermediate in the second zone to thereby form a Si-containing film;

the Si precursor being selected from the group consisting of

4. The method of claim 3 in which the Si-containing film is a crosslinked Si-containing film.

5. The method of claim 3 in which the Si-containing film comprises a recurring unit selected from the group consisting of —

SO₂—

, —

Si(R⁴R⁵)O—

, and —

(SiO₂)—

(Si(R⁴R⁵)O)—

.

6. The method of claim 3 in which the polymerizing of the activated Si-containing intermediate is conducted in the presence of an oxygen source.

7. The method of claim 6 in which the oxygen source is selected from the group consisting of O₂, O₃, N2O and mixtures thereof.

8. The method of claim 3 further comprising oxidizing the Si-containing film.

9. The method of claim 3 further comprising annealing the Si-containing film.

10. The method of claim 9 in which at least a part of the annealing is conducted under an inert gas.

11. The method of claim 9 in which at least a part of the annealing is conducted under a gas selected from the group consisting of nitrogen, helium, hydrogen, a nitrogen/helium mixture, and a nitrogen/hydrogen mixture.

12. The method of claim 9 wherein annealing comprises exposing the Si-containing film to an oxygen-containing gas.

13. The method of claim 9 further comprising oxidizing the Si-containing film after the annealing.

14. The method of claim 9 further comprising introducing a porogen to the second zone during the polymerizing of the activated Si-containing intermediate.

15. The method of claim 14 in which the Si-containing film comprises the porogen.

16. The method of claim 15 in which the annealing removes at least a portion of the porogen from the Si-containing film.

17. The method of claim 3 in which a first zone temperature is at least about 25°

C. higher than a second zone temperature.

18. The method of claim 3 in which the transporting is conducted through a transport region situated between the first zone and the second zone.

19. The method of claim 18 in which a transport region temperature is higher than a second zone temperature.

20. A method for forming a film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing film on the substrate, the Si-containing film comprising a least a portion of the porogen; and

pyrolyzing a Si precursor to form the pyrolyzed Si precursor;

in which the Si precursor is selected from the group consisting of

21. The method of claim 20 in which the porogen is selected from the group consisting of optionally halogenated C₂-C₁₀ alcohol, optionally halogenated C₂-C₁₀ diol, optionally halogenated C₂-C₁₀ ether, optionally halogenated C₂-C₁₀ ketone, optionally halogenated C₂-C₁₀ ester, optionally halogenated C₂-C₁₀ aldehyde, optionally halogenated C₁-C₁₀ hydrocarbon, optionally halogenated C₂-C₁₀ carboxylic acid, optionally halogenated C₂-C₁₀ anhydride, carbon monoxide, and carbon dioxide.

22. The method of claim 21 in which the porogen is selected from the group consisting of dimethyl oxalate, di-tertiarybutyl oxalate, carbon tetrabromide, benzene, methanol and t-butanol.

23. The method of claim 20 in which the at least a portion of the porogen is chemically bonded to the Si-containing film.

24. The method of claim 20 in which the at least a portion of the porogen is not chemically bonded to the Si-containing film.

25. The method of claim 20 in which substantially all of the porogen is not chemically bonded to the Si-containing film.

26. The method of claim 20, further comprising heating the Si-containing film to a temperature in the range of about 50°

C. to about 600°

C.

27. The method of claim 26 in which the heating of the Si-containing film is conducted in the presence of an inert gas.

28. The method of claim 26 in which the heating of the Si-containing film is conducted in the presence of a gas selected from the group consisting of nitrogen, helium, hydrogen, a nitrogen/helium mixture, and a nitrogen/hydrogen mixture.

29. The method of claim 26 in which the heating of the Si-containing film is conducted at a pressure of about 600 Torr or less.

30. The method of claim 26 in which the heating of the Si-containing film is conducted in the presence of an oxygen-containing gas.

31. The method of claim 30 in which the oxygen-containing gas is selected from the group consisting of O₂, O₃, N₂O and mixtures thereof.

32. The method of claim 26 in which the heating of the Si-containing film removes at least a part of the porogen from the Si-containing film.

33. A method for forming a film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing film on the substrate, the Si-containing film comprising a least a portion of the porogen; and

pyrolyzing a Si precursor to form the pyrolyzed Si precursor;

in which the Si precursor is selected from the group consisting of

34. A method for forming a porous film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing polymer;

depositing the Si-containing polymer and the porogen on the substrate to thereby form a porogen-containing Si-containing film on the substrate; and

removing at least a portion of the porogen from the porogen-containing Si-containing film to thereby form a porous Si-containing film on the substrate, the porous Si-containing film comprising the Si-containing polymer;

in which the Si precursor is selected from the group consisting of

35. The method of claim 34 further comprising pyrolyzing a Si precursor to form the pyrolyzed Si precursor.

36. The method of claim 34 in which the porogen is selected from the group consisting of optionally halogenated C₂-C₁₀ alcohol, optionally halogenated C₂-C₁₀ diol, optionally halogenated C₂-C₁₀ ether, optionally halogenated C₂-C₁₀ ketone, optionally halogenated C₂-C₁₀ ester, optionally halogenated C₂-C₁₀ aldehyde, optionally halogenated C₁-C₁₀ hydrocarbon, optionally halogenated C₂-C₁₀ carboxylic acid, optionally halogenated C₂-C₁₀ anhydride, carbon monoxide, and carbon dioxide.

37. The method of claim 34 in which the porogen is selected from the group consisting of dimethyl oxalate, di-tertiarybutyl oxalate, carbon tetrabromide, benzene, methanol and t-butanol.

38. The method of claim 34 in which the porous Si-containing film is a graded porous Si-containing film having a degree of porosity that changes as a function of depth in the film.

39. The method of claim 38 in which the degree of porosity of the graded porous Si-containing film is lower near a surface of the graded porous Si-containing film as compared to the degree of porosity near the center of the graded porous Si-containing film.

40. The method of claim 34, further comprising heating the Si-containing film to a temperature in the range of about 50°

C. to about 600°

C.

41. The method of claim 40 in which the heating of the Si-containing film is conducted in the presence of an inert gas.

42. The method of claim 40 in which the heating of the Si-containing film is conducted in the presence of a gas selected from the group consisting of nitrogen, helium, hydrogen, a nitrogen/helium mixture, and a nitrogen/hydrogen mixture.

43. The method of claim 40 in which the heating of the Si-containing film is conducted at a pressure of about 600 Torr or less.

44. The method of claim 40 in which the heating of the Si-containing film is conducted at a pressure in the range of about 760 Torr to about 7,600 Torr.

45. The method of claim 40 in which the heating of the Si-containing film is conducted at a pressure that is varied between about 7,600 Torr and about 1×

10<sup>−

4</sup> Torr during the heating.

46. The method of claim 40 in which the heating of the Si-containing film is conducted in the presence of an oxygen-containing gas.

47. The method of claim 46 in which the oxygen-containing gas is selected from the group consisting of O₂, O₃, N2O and mixtures thereof.

48. The method of claim 34 in which removing the at least a portion of the porogen from the porogen-containing Si-containing film comprises applying a pressure of about 600 Torr or less to the porogen-containing Si-containing film.

50. The method of claim 34 in which the porous Si-containing film is a graded porous Si-containing film having a degree of porosity that changes as a function of depth in the film.

51. The method of claim 50 in which the degree of porosity of the graded porous Si-containing film is lower near a surface of the graded porous Si-containing film as compared to the degree of porosity near the center of the graded porous Si-containing film.

52. The method of claim 34 in which removing the at least a portion of the porogen from the porogen-containing Si-containing film comprises heating the porogen-containing Si-containing film.

53. The method of claim 52 comprising heating the porogen-containing Si-containing film to a temperature in the range of about 50°

C. to about 600°

C.

54. The method of claim 52 in which the heating of the porogen-containing Si-containing film is conducted in the presence of an inert gas.

55. The method of claim 52 in which the heating of the porogen-containing Si-containing film is conducted in the presence of a gas selected from the group consisting of nitrogen, helium, hydrogen, a nitrogen/helium mixture, and a nitrogen/hydrogen mixture.

56. The method of claim 52 in which the heating of the porogen-containing Si-containing film is conducted at a pressure of about 600 Torr or less.

57. The method of claim 52 in which the heating of the porogen-containing Si-containing film is conducted at a pressure in the range of about 760 Torr to about 7,600 Torr.

58. The method of claim 52 in which the heating of the porogen-containing Si-containing film is conducted at a pressure that is varied between about 7,600 Torr and about 1×

10<sup>−

4</sup> Torr during the heating.

59. The method of claim 52 in which the heating of the Si-containing film is conducted in the presence of an oxygen-containing gas.

60. The method of claim 59 in which the oxygen-containing gas is selected from the group consisting of O₂, O₃, N₂O and mixtures thereof.

49. A method for forming a porous film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing polymer;

depositing the Si-containing polymer and the porogen on the substrate to thereby form a porogen-containing Si-containing film on the substrate; and

removing at least a portion of the porogen from the porogen-containing Si-containing film to thereby form a porous Si-containing film on the substrate, the porous Si-containing film comprising the Si-containing polymer;

in which the porogen comprises di-tertiarybutyl oxalate.

61. A method for forming a porous film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing polymer;

depositing the Si-containing polymer and the porogen on the substrate to thereby form a porogen-containing Si-containing film on the substrate; and

removing at least a portion of the porogen from the porogen-containing Si-containing film to thereby form a porous Si-containing film on the substrate, the porous Si-containing film comprising the Si-containing polymer;

in which the Si precursor is selected from the group consisting of;

62. A method for forming a porous film, comprising:

transporting a pyrolyzed Si precursor to a substrate;

polymerizing the pyrolyzed Si precursor in the presence of a porogen to form a Si-containing polymer;

depositing the Si-containing polymer and the porogen on the substrate to thereby form a porogen-containing Si-containing film on the substrate; and

removing at least a portion of the porogen from the porogen-containing Si-containing film to thereby form a porous Si-containing film on the substrate, the porous Si-containing film comprising the Si-containing polymer;

in which the porogen comprises di-tertiarybutyl oxalate.