Polymeric antireflective coatings deposited by plasma enhanced chemical vapor deposition

• US 20030219541A1
• Filed: 04/09/2003
• Published: 11/27/2003
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Brewer Science Inc.
• Original Assignee: Brewer Science Inc.
• Inventors: Sabnis, Ram W., Guerrero, Douglas J., Shih, Wu-Sheng
• Granted Patent: US 7,132,219 B2
• Time in Patent Office: Days
• US Class Current: 427/385.5
• CPC Class Codes: G02B 1/11 Anti-reflection coatings
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G03F 7/091 characterised by antireflection means or light filtering or absorbing means, e.g. anti-halation, contrast enhancement

Abstract

An improved method for applying polymeric antireflective coatings to substrate surfaces and the resulting precursor structures are provided. Broadly, the methods comprise plasma enhanced chemical vapor depositing (PECVD) a polymer on the substrate surfaces. The most preferred starting monomers are 4-fluorostyrene, 2,3,4,5,6-pentafluorostyrene, and allylpentafluorobenzene. The PECVD processes comprise subjecting the monomers to sufficient electric current and pressure so as to cause the monomers to sublime to form a vapor which is then changed to the plasma state by application of an electric current. The vaporized monomers are subsequently polymerized onto a substrate surface in a deposition chamber. The inventive methods are useful for providing highly conformal antireflective coatings on large surface substrates having super submicron (0.25 μm or smaller) features. The process provides a much faster deposition rate than conventional chemical vapor deposition (CVD) methods, is environmentally friendly, and is economical

Claims

1. A method of forming a precursor for use in manufacturing microelectronic, optoelectronic, photonic, or microelectromechanical system devices, said method comprising the steps of:

providing a quantity of monomers and a substrate having a surface onto which a coating layer is to be applied, said monomers having the formula

wherein;

each R is individually selected from the group consisting of alkyl groups;

each X is individually selected from the group consisting of cyano groups, nitroso groups, and the halogens;

m is 0-10; and

n is 1-12;

forming said monomers into a plasma; and

depositing said plasma monomers on said substrate surface so as to form the coating layer thereon.

2. The method of claim 1, wherein said ringed structure is selected from the group consisting of moieties of benzene, naphthalene, anthracene, acridine, furan, thiophene, pyrrole, pyridine, pyridazine, pyrimidine, pyrazine, thiazine, oxazine, thiazole, oxazole, pyrazole, oxadiazole, quinazoline, and quinoxaline.

3. The method of claim 2, wherein said monomer has the formula

4. The method of claim 1, wherein each R is individually selected from the group consisting of C₁-C₂₀ alkyl groups.

5. The method of claim 4, wherein each R is individually selected from the group consisting of methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and amyl groups.

6. The method of claim 1, wherein said monomers are selected from the group consisting of xylene, tolulene, and derivatives thereof.

7. The method of claim 6, wherein said monomers are selected from the group consisting of 2-fluorotoluene, 3-fluorotoluene, 4-fluorotoluene, 2-chlorotoluene, 3-chlorotoluene, 4-chlorotoluene, 2-bromotoluene, 3-bromotoluene, 4-bromotoluene, 2-iodotoluene, 3-iodotoluene, 4-iodotoluene, 2-ethyltoluene, 3-ethyltoluene, 4-ethyltoluene, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 3-nitrotoluene, 3-nitrotoluene, 4-nitrotoluene, o-xylene, m-xylene, p-xylene, 2-bromo-m-xylene, 2-bromo-p-xylene, 3-bromo-o-xylene, 4-bromo-o-xylene, 4-bromo-m-xylene, 5-bromo-m-xylene, 4-tert-butyltoluene, 4-tert-butyl-o-xylene, 5-tert-butyl-m-xylene, 2-chloro-3-nitrotoluene, 2-chloro-4-nitrotoluene, 2-chloro-6-nitrotoluene, 3-chloro-4-nitrotoluene, 4-chloro-2-nitrotoluene, 4-chloro-3-nitrotoluene, 5-chloro-2-nitrotoluene, 2-fluoro-4-nitrotoluene, 2-fluoro-5-nitrotoluene, 2-fluoro-6-nitrotoluene, 3-fluoro-4-nitrotoluene, 4-fluoro-2-nitrotoluene, 5-fluoro-2-nitrotoluene, 2-fluoro-m-xylene, 3-fluoro-o-xylene, 2-chloro-m-xylene, 2-chloro-p-xylene, 3-chloro-o-xylene, 4-chloro-o-xylene, and mixtures thereof.

8. The method of claim 1, further including the step of applying a photoresist layer to said coating layer to yield an integrated circuit precursor structure.

9. The method of claim 1, wherein said monomers have a melting or boiling point of less than about 450°

C.

10. The method of claim 9, wherein said monomers have a melting or boiling point of less than about 100°

C.

11. The method of claim 1, wherein said substrate is selected from the group consisting of silicon, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, SiGe, and tantalum nitrite wafers.

12. The method of claim 1, wherein said plasma forming step comprises subjecting said monomers to an electric current and pressure.

13. The method of claim 12, wherein said electric current is from about 0.1-10 amps.

14. The method of claim 12, wherein said electric current is applied in pulses.

15. The method of claim 12, wherein said pressure is from about 5-200 mTorr.

16. The method of claim 1, wherein said coating layer on said substrate surface after said depositing step has a thickness of from about 100-5000 Å

.

17. The method of claim 8, wherein said layer is substantially insoluble in solvents utilized in said photoresist layer.

18. The method of claim 8, further including the steps of:

exposing at least a portion of said photoresist layer to activating radiation;

developing said exposed photoresist layer; and

etching said developed photoresist layer.

19. The method of claim 1, wherein said coating layer deposited on said substrate surface is an antireflective layer which absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

20. The method of claim 1, wherein said coating layer deposited on said substrate surface is an antireflective layer which has a k value of at least about 0.1 at light having a wavelength of about 193 nm.

21. The method of claim 1, wherein said coating layer deposited on said substrate surface is an antireflective layer which has an n value of at least about 1.1 at light having a wavelength of about 193 nm.

22. The method of claim 1, wherein said depositing step comprises depositing said monomers on said surface at a rate of at least about 100 Å

/min. on an eight-inch round substrate.

23. The method of claim 1, wherein said plasma monomers polymerize during said depositing step.

24. A precursor structure formed during the process of manufacturing microelectronic, optoelectronic, photonic, or microelectromechanical system devices, said structure comprising:

a substrate having a surface; and

a coating layer on said surface, said coating layer being formed by the steps of;

providing a quantity of monomers having the formula

wherein;

each R is individually selected from the group consisting of alkyl groups;

each X is individually selected from the group consisting of cyano groups, nitroso groups, and the halogens;

m is 0-10; and

n is 1-12;

forming said monomers into a plasma; and

depositing said plasma monomers on said substrate surface so as to form the coating layer thereon.

25. The structure of claim 24, wherein said ringed structure is selected from the group consisting of moieties of benzene, naphthalene, anthracene, acridine, furan, thiophene, pyrrole, pyridine, pyridazine, pyrimidine, pyrazine, thiazine, oxazine, thiazole, oxazole, pyrazole, oxadiazole, quinazoline, and quinoxaline.

26. The structure of claim 25, wherein said monomer has the formula

27. The structure of claim 24, wherein each R is individually selected from the group consisting of C₁-C₂₀ alkyl groups.

28. The structure of claim 27, wherein each R is individually selected from the group consisting of methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl, and amyl groups.

29. The structure of claim 24, wherein said monomers are selected from the group consisting of xylene, tolulene, and derivatives thereof.

30. The structure of claim 29, wherein said monomers are selected from the group consisting of 2-fluorotoluene, 3-fluorotoluene, 4-fluorotoluene, 2-chlorotoluene, 3-chlorotoluene, 4-chlorotoluene, 2-bromotoluene, 3-bromotoluene, 4-bromotoluene, 2-iodotoluene, 3-iodotoluene, 4-iodotoluene, 2-ethyltoluene, 3-ethyltoluene, 4-ethyltoluene, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 3-nitrotoluene, 3-nitrotoluene, 4-nitrotoluene, o-xylene, m-xylene, p-xylene, 2-bromo-m-xylene, 2-bromo-p-xylene, 3-bromo-o-xylene, 4-bromo-o-xylene, 4-bromo-m-xylene, 5-bromo-m-xylene, 4-tert-butyltoluene, 4-tert-butyl-o-xylene, 5-tert-butyl-m-xylene, 2-chloro-3-nitrotoluene, 2-chloro-4-nitrotoluene, 2-chloro-6-nitrotoluene, 3-chloro-4-nitrotoluene, 4-chloro-2-nitrotoluene, 4-chloro-3-nitrotoluene, 5-chloro-2-nitrotoluene, 2-fluoro-4-nitrotoluene, 2-fluoro-5-nitrotoluene, 2-fluoro-6-nitrotoluene, 3-fluoro-4-nitrotoluene, 4-fluoro-2-nitrotoluene, 5-fluoro-2-nitrotoluene, 2-fluoro-m-xylene, 3-fluoro-o-xylene, 2-chloro-m-xylene, 2-chloro-p-xylene, 3-chloro-o-xylene, 4-chloro-o-xylene, and mixtures thereof.

31. The structure of claim 24, said structure further comprising a photoresist layer on said coating layer.

32. The structure of claim 24, wherein said substrate is selected from the group consisting of silicon, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, SiGe, and tantalum nitrite wafers.

33. The structure of claim 24, wherein the antireflective coating layer on said substrate surface has a thickness of from about 100-5000 Å

.

34. The structure of claim 31, wherein said antireflective coating layer is substantially insoluble in solvents utilized in said photoresist layer.

35. The structure of claim 24, wherein said coating layer is an antireflective layer which absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

36. The structure of claim 24, wherein said coating layer is an antireflective layer which has a k value of at least about 0.1 at light having a wavelength of about 193 nm.

37. The structure of claim 24, wherein said coating layer is an antireflective layer which has an n value of at least about 1.1 at light having a wavelength of about 193 nm.

38. The structure of claim 24, wherein said coating layer has less than about 0.1 defects per cm² of substrate surface.

39. A method of forming a precursor for use in manufacturing integrated circuits comprising the steps of:

providing a quantity of monomers and a substrate having a surface onto which an antireflective coating is to be applied;

forming said monomers into a plasma;

depositing said plasma monomers on said substrate surface so as to form an antireflective coating layer; and

applying a photoresist layer to said antireflective coating layer to yield the circuit precursor.

40. The method of claim 39, wherein said monomers comprising a light attenuating moiety and an unsaturated moiety.

41. The method of claim 40, wherein said light attenuating moiety is a cyclic compound.

42. The method of claim 41, wherein said light attenuating moiety is selected from the group consisting of benzene, naphthalene, anthracene, acridine, furan, thiophene, pyrrole, pyridine, pyridazine, pyrimidine, and pyrazine.

43. The method of claim 41, wherein said light attenuating moiety comprises a group selected from the group consisting of cyano groups, nitroso groups, and halogens.

44. The method of claim 39, wherein said monomers have a melting or boiling point of less than about 200°

C.

45. The method of claim 40, wherein said monomers are selected from the group consisting of styrene and substituted derivatives thereof, allylbenzene and substituted derivatives thereof.

46. The method of claim 40, wherein said monomers are selected from the group consisting of 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-fluorostyrene, 3-fluorostyrene, 4-fluorostyrene, 2-bromostyrene, 3-bromostyrene, 4-bromostyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 2-nitrostyrene, 3-nitrostyrene, 4-nitrostyrene, 3,5-bis(trifluoromethyl)styrene, trans-2-chloro-6-fluoro-β

-nitrostyrene, decafluoroallylbenzene, 2,6-difluorostyrene, ethyl 7-[1-(4-fluorophenyl)-4-isopropyl-2-phenyl-1H-imidazol-5-yl)-5-hydroxy-3-oxo-trans-6-heptenoate, flunarizine dihydrochloride, trans-4-fluoro-β

-nitrostyrene, 2-fluorostyrene, 3-fluorostyrene, β

-nitro-4-(trifluoromethoxy)styrene, trans-β

-nitro-2-(trifluoromethyl)styrene, trans-β

-nitro-3-(trifluoromethyl)styrene, β

-nitro-4-(trifluoromethyl)styrene, trans-2,3,4,5,6-pentafluoro-β

-nitrostyrene, trans-1,1,1-trifluoro-4-(3-indolyl)-3-buten-2-one, a-(trifluoromethyl)-styrene, 2-(trifluoromethyl)styrene, 3-(trifluoromethyl)styrene, 4-(trifluoromethyl)-styrene, and 3,3,3-trifluoro-1-(phenylsulfonyl)-1-propene.

47. The method of claim 39, wherein said substrate is selected from the group consisting of silicon, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, SiGe, and tantalum nitrite wafers.

48. The method of claim 39, wherein said plasma forming step comprises subjecting said antireflective compound to an electric current and pressure.

49. The method of claim 48, wherein said electric current is from about 0.1-10 amps.

50. The method of claim 48, wherein said electric current is applied in pulses.

51. The method of claim 48, wherein said pressure is from about 50-200 mTorr.

52. The method of claim 39, wherein the antireflective coating layer on said substrate surface after said depositing step has a thickness of from about 300-5000 Å

.

53. The method of claim 39, wherein said antireflective coating layer is substantially insoluble in solvents utilized in said photoresist layer.

54. The method of claim 39, further including the steps of:

exposing at least a portion of said photoresist layer to activating radiation;

developing said exposed photoresist layer; and

etching said developed photoresist layer.

55. The method of claim 39, wherein the antireflective coating layer deposited on said substrate surface absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

56. The method of claim 39, wherein the antireflective coating layer has a k value of at least about 0.1 at light of a wavelength of 193 nm.

57. The method of claim 39, wherein the antireflective coating layer has an n value of at least about 1.1 at light of a wavelength of 193 nm.

58. The method of claim 39, wherein the rate of deposition of said monomers on said surface is at least about 100 Å

/min. on an eight-inch round substrate.

59. The method of claim 39, wherein said plasma monomers polymerize during said depositing step.

60. A precursor structure formed during the course of the integrated circuit manufacturing process, said structure comprising:

a substrate having a surface;

an antireflective coating layer on said surface, said antireflective coating layer being formed on said surface by a plasma enhanced chemical vapor deposition process; and

a photoresist layer on said antireflective coating layer.

61. The structure of claim 60, wherein said antireflective coating layer comprises a polymer includes recurring monomers comprising a light attenuating moiety and an unsaturated moiety.

62. The structure of claim 61, wherein said antireflective coating layer consists essentially of a polymer includes recurring monomers comprising a light attenuating moiety and an unsaturated moiety.

63. The structure of claim 61, wherein said light attenuating moiety is a cyclic compound.

64. The structure of claim 63, wherein said light attenuating moiety is selected from the group consisting of benzene, naphthalene, anthracene, acridine, furan, thiophene, pyrrole, pyridine, pyridazine, pyrimidine, and pyrazine.

65. The structure of claim 63, wherein said light attenuating moiety comprises a group selected from the group consisting of cyano groups, nitroso groups, and halogens.

66. The structure of claim 61, wherein said monomers are selected from the group consisting of styrene and substituted derivatives thereof, allylbenzene and substituted derivatives thereof.

67. The structure of claim 61, wherein said monomers are selected from the group consisting of 2-methoxystyrene, 3-methoxystyrene, 4-methoxystyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-fluorostyrene, 3-fluorostyrene, 4-fluorostyrene, 2-bromostyrene, 3-bromostyrene, 4-bromostyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 2-nitrostyrene, 3-nitrostyrene, 4-nitrostyrene, 3,5-bis(trifluoromethyl)styrene, trans-2-chloro-6-fluoro-β

-nitrostyrene, decafluoroallylbenzene, 2,6-difluorostyrene, ethyl 7-[1-(4-fluorophenyl)-4-isopropyl-2-phenyl-1H-imidazol-5-yl)-5-hydroxy-3-oxo-trans-6-heptenoate, flunarizine dihydrochloride, trans-4-fluoro-13-nitrostyrene, 2-fluorostyrene, 3-fluorostyrene, β

-nitro-4-(trifluoromethoxy)styrene, trans-β

-nitro-2-(trifluoromethyl)styrene, trans-β

-nitro-3-(trifluoromethyl)styrene, β

-nitro-4-(trifluoromethyl)styrene, trans-2,3,4,5,6-pentafluoro-β

-nitrostyrene, trans-1,1,1-trifluoro-4-(3-indolyl)-3-buten-2-one, a-(trifluoromethyl)-styrene, 2-(trifluoromethyl)styrene, 3-(trifluoromethyl)styrene, 4-(trifluoromethyl)-styrene, and 3,3,3-trifluoro-1-(phenylsulfonyl)-1-propene.

68. The structure of claim 60, wherein said substrate is selected from the group consisting of silicon, aluminum, tungsten, tungsten silicide, gallium arsenide, germanium, tantalum, SiGe, and tantalum nitrite wafers.

69. The structure of claim 60, wherein the antireflective coating layer on said substrate surface has a thickness of from about 300-5000 Å

.

70. The structure of claim 60, wherein said antireflective coating layer is substantially insoluble in solvents utilized in said photoresist layer.

71. The structure of claim 60, wherein the antireflective coating layer absorbs at least about 90% of light at a wavelength of from about 150-500 nm.

72. The structure of claim 60, wherein the antireflective coating layer has a k value of at least about 0.1 at light of a wavelength of 193 nm.

73. The structure of claim 60, wherein the antireflective coating layer has an n value of at least about 1.1 at light of a wavelength of 193 nm.