Organosilicon precursors for interlayer dielectric films with low dielectric constants

• US 6,583,048 B2
• Filed: 08/31/2001
• Issued: 06/24/2003
• Est. Priority Date: 01/17/2001
• Status: Expired due to Term

• Current Assignee: Versum Materials US Inc.
• Original Assignee: Air Products and Chemicals Incorporated (Linde Plc)
• Inventors: Vincent, Jean Louise, Beck, Scott Edward, Vrtis, Raymond Nicholas, Withers, Howard Paul Jr., OʼNeill, Mark Leonard
• Primary Examiner(s): Nelms, David
• Assistant Examiner(s): Le, Thao P
• Application Number:
  US09/944,042
• Publication Number:
  US 20020142579A1
• Time in Patent Office: 662 Days
• Field of Search: 438/623, 438/743, 438/763, 438/770, 438/773, 438/622
• US Class Current: 438/623
• CPC Class Codes: B05D 1/60 Deposition of organic layers from vapour phase vapour phase deposition in general C23C14/00, C23C16/00
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02131 the material being halogen doped silicon oxides, e.g. FSG
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/3121 Layers comprising organo-silicon compounds
• CPC Class Codes: H01L 21/31629 Deposition of halogen doped silicon oxide, e.g. fluorine doped silicon oxide
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC

Abstract

A method of forming a low dielectric constant interlayer dielectric film on a substrate by reacting, under chemical vapor deposition conditions sufficient to deposit the film on the substrate, an organosilicon precursor comprising a silyl ether, a silyl ether oligomer, or an organosilicon compound containing one or more reactive groups, to form an interlayer dielectric film having a dielectric constant of 3.5 or less. The films formed by the above method.

Claims

1. A method of forming a low dielectric constant interlayer dielectric film comprising reacting, under chemical vapor deposition conditions sufficient to deposit a film on a substrate, an organosilicon precursor comprising one or more silyl ether, represented by one or more of structures I through III, or a silyl ether oligomer, represented by structure IV:

3. The method of claim 1 where the organosilicon compound is selected from the group consisting of phenoxytrimethylsilane, 2-tert-butyl-phenoxytrimethylsilane, dimethylethoxysilane, dimethoxymethylsilane, 1,2-bis(trimethylsiloxy)ethane, 1,4-bis(trimethylsiloxy)benzene, 1,2-bis(trimethylsiloxy)cyclobutene, 1,2-dimethoxytetramethyldisilane, pentafluorophenoxytrimethylsilane, 1,1,1-trifluoroethoxytrimethylsilane, 1,1,1-trifuoroethoxydimethylsilane, dimethyoxymethylfluorosilane, 1,2-bis(trimethylsiloxy)tetrafluoroethane, 1,4-(trifluorosiloxy)tetrafluorobenzene, 1,2-difluoro-1,2-dimethoxydimethyldisilane, and mixtures thereof.

5. The method of claim 1 wherein the interlayer dielectric film is represented by the formula, Si_aO_bC_cH_dF_e, wherein, on an atomic % basis, a=10-35%, b=1-66%, c=1-35%, d=0-60%, and e=0-25%, such that a+b+c+d+e=100%.

6. The method of claim 1 wherein the chemical vapor deposition conditions are plasma enhanced chemical vapor deposition conditions.

7. The method of claim 1 wherein the chemical vapor deposition conditions are thermal chemical vapor deposition conditions.

8. The method of claim 1 wherein the substrate is a silicon wafer.

9. The method of claim 1 wherein the interlayer dielectric film has one or more of the bond types selected from Si—

O—

C, Si—

O—

Si, Si—

C, Si—

F, Si—

H, C—

O, C—

H, and C—

F.

10. The method of claim 1 wherein the dielectric constant is 3 or less.

11. The method of claim 1 wherein the interlayer dielectric film is porous.

12. The method of claim 1 wherein the chemical vapor deposition conditions include the use of an oxidant selected from the group consisting of O₂, O₃, H₂O₂, N₂O, and mixtures thereof.

13. The method of claim 1 wherein the chemical vapor deposition conditions exclude the use of an oxidant.

14. The method of claim 1 wherein the chemical vapor deposition conditions include the use of one or more inert gases selected from the group consisting of helium, neon, argon, krypton, xenon, nitrogen.

15. The method of claim 1 wherein the one or more reactive substances is selected from the group consisting of a gaseous or liquid organic substance, ammonia, hydrogen, carbon dioxide, carbon monoxide, a fluorocarbon, and mixtures thereof.

16. The method of claim 15 wherein the gaseous or liquid organic substance is selected from the group consisting of methane, ethane, ethene, ethyne, propane, propene, butene, benzene, naphthalene, toluene, styrene, and mixtures thereof, and the fluorocarbon is selected from the group consisting of CF₄, C₂F₆, C₄F₆, C₆F₆, and mixtures thereof.

17. The method of claim 1 wherein the film is deposited on the substrate as an insulation layer, an interlayer dielectric layer, an intermetal dielectric layer, a capping layer, a chemical-mechanical planarization or etch stop layer, a barrier layer, or an adhesion layer in an integrated circuit.

31. The method of claim 1 wherein the chemical vapor deposition conditions are plasma enhanced chemical vapor deposition conditions and the one or more silyl ether is represented by structure II.

32. A film formed by the method of claim 1.

34. A film formed by the method of claim 31.

35. The film of claim 32, wherein said film is porous.

36. The film of claim 35 having a pore size of 5 nm or less equivalent spherical diameter, as determined by small angle neutron scattering or positron annihilation lifetime spectroscopy.

37. The film of claim 35 having a pore size of 2.5 nm or less equivalent spherical diameter, as determined by small angle neutron scattering or positron annihilation lifetime spectroscopy.

38. The film of claim 32 wherein said film has a density of 2 g/cc or less.

39. The film of claim 32 wherein said film has a density of 1.5 g/cc or less.

40. The film of claim 32 wherein said film has a dielectric constant of 2.5 to 3.5 and a Young'"'"'s modulus greater than 3 GPa and/or a nanoindentation hardness greater than 0.5 GPa.

2. A method of forming a low dielectric constant interlayer dielectric film comprising reacting, under chemical vapor deposition conditions sufficient to deposit a film on a substrate, an organosilicon precursor comprising one or more organosilicon compound containing one or more reactive side group selected from the group consisting of a C2 to C10 epoxide, a C2 to C8 carboxylate, a C2 to C8 alkyne, a C4 to C8 diene, a C3 to C5 strained cyclic group, and a C4 to C10 group that can sterically hinder or strain the organosilicon precursor;

optionally together with one or more additional reactive substance;

to form an interlayer dielectric film having a dielectric constant of 3.5 or less.

4. The method of claim 2 wherein the organosilicon precursor is selected from the group consisting of 3-glycidoxypropyltrimethyoxysilane, trimethylsilylacetylene, bis(trimethylsilyl)acetylene, trimethylsiloxyacetylene, 1-(trimethylsiloxy)-1,3-butadiene, 2-(trimethylsilyl)-1,3-butadiene, trimethylsilylcyclopentadiene, 4-(tert-butylphenyl)silane, 1,2-(dimethylsilyl)benzene, trimethylsilylacetate, di-tert-butoxydiacetoxy silane, and mixtures thereof.

18. The method of claim 2 wherein the interlayer dielectric film is represented by the formula, Si_aO_bC_cH_dF_e, wherein, on an atomic % basis, a=10-35%, b=1-66%, c=1-35%, d=0-60%, and e=0-25%, such that a+b+c+d+e=100%.

19. The method of claim 2 wherein the chemical vapor deposition conditions are plasma enhanced chemical vapor deposition conditions.

20. The method of claim 2 wherein the chemical vapor deposition conditions are thermal chemical vapor deposition conditions.

21. The method of claim 2 wherein the substrate is a silicon wafer.

22. The method of claim 2 wherein the interlayer dielectric film has one or more of the bond types selected from Si—

O—

C, Si—

O—

Si, Si—

C, Si—

F, Si—

H, C—

O, C—

H, and C—

F.

23. The method of claim 2 wherein the dielectric constant is 3 or less.

24. The method of claim 2 wherein the interlayer dielectric film is porous.

25. The method of claim 2 wherein the chemical vapor deposition conditions include the use of an oxidant selected from the group consisting of O₂, O₃, H₂O₂, N₂O, and mixtures thereof.

26. The method of claim 2 wherein the chemical vapor deposition conditions exclude the use of an oxidant.

27. The method of claim 2 wherein the chemical vapor deposition conditions include the use of one or more inert gases selected from the group consisting of helium, neon, argon, krypton, xenon, nitrogen.

28. The method of claim 2 wherein the one or more reactive substances selected from the group consisting of a gaseous or liquid organic substance, ammonia, hydrogen, carbon dioxide, carbon monoxide, a fluorocarbon, and mixtures thereof.

29. The method of claim 28 wherein the gaseous or liquid organic substance is selected from the group consisting of methane, ethane, ethene, ethyne, propane, propene, butene, benzene, naphthalene, toluene, styrene, and mixtures thereof, and the fluorocarbon is selected from the group consisting of CF₄, C₂F₆, C₄F₆, C₆F₆, and mixtures thereof.

30. The method claim 2 wherein the film is deposited on the substrate as an insulation layer, an interlayer dielectric layer, an intermetal dielectric layer, a capping layer, a chemical-mechanical planarization or etch stop layer, a barrier layer, or an adhesion layer in an integrated circuit.

33. A film formed by the method of claim 2.

41. The film of claim 33, wherein said film is porous.

42. The film of claim 41 having a pore size of 5 nm or less equivalent spherical diameter, as determined by small angle neutron scattering or positron annihilation lifetime spectroscopy.

43. The film of claim 41 having a pore size of 2.5 nm or less equivalent spherical diameter, as determined by small angle neutron scattering or positron annihilation lifetime spectroscopy.

44. The film of claim 33 wherein said film has a density of 2 g/cc or less.

45. The film of claim 33 wherein said film has a density of 1.5 g/cc or less.

46. The film of claim 33 wherein said film has a dielectric constant of 2.5 to 3.5 and a Young'"'"'s modulus greater than 3 GPa and/or a nanoindentation hardness greater than 0.5 GPa.

47. A method of forming a low dielectric constant interlayer dielectric film comprising reacting, under chemical vapor deposition conditions sufficient to deposit a film on a substrate, an organosilicon precursor comprising one or more silyl ether selected train the group consisting of diethoxymethylsilane, dimethylethoxysilane, dimethoxymethylsilane, dimethylmethoxysilane, phenoxydimethylsilane, diphenoxymethylsilane, dimethoxyphenylsilane, diethoxycyclohexyrsilane, tert-butoxydimethylsilane, and di(tert-butoky)methylsilane;

to form an interlayer dielectric film having a dielectric constant of about 3.5 or less.

48. The method of claim 47 the chemical vapor deposition conditions are plasma enhanced chemical vapor deposition conditions.

49. The method of claim 48 wherein the plasma enhanced chemical vapor deposition conditions include the use of one or more gases selected from the group consisting of carbon dioxide, argon, helium, nitrogen, oxygen, nitrous oxide, hydrogen peroxide and ozone.

50. The method of claim 48 wherein the organosilicon precursor is diethoxymethylsilane.

51. The method of claim 50 wherein the plasma enhanced chemical vapor deposition conditions include the use of carbon dioxide or helium.

53. A film formed by the method of claim 47.

54. A film formed by the method of claim 48.

55. A film formed by the method of claim 50.

52. A method of forming a low dielectric constant interlayer dielectric film which comprises reading diethoxymethylsilane, under plasma vapor deposition conditions sufficient to deposit a film on a substrate, in the presence of carbon dioxide or helium, to form an interlayer dielectric film having a dielectric constant of about 2.5 to 3.5.

56. A film formed by the method of claim 52.