Method of forming a carbon polymer film using plasma CVD

• US 7,504,344 B2
• Filed: 06/30/2005
• Issued: 03/17/2009
• Est. Priority Date: 08/09/2004
• Status: Active Grant

• Current Assignee: ASM Japan K.K. (ASM International NV)
• Original Assignee: ASM Japan K.K. (ASM International NV)
• Inventors: Umemoto, Seijiro, Lee, Jea Sik, Matsuki, Nobuo, Morisada, Yoshinori
• Primary Examiner(s): Ghyka; Alexander G
• Application Number:
  US11/172,031
• Publication Number:
  US 20060084280A1
• Time in Patent Office: 1,356 Days
• Field of Search: 438/680, 438/758, 438/780
• US Class Current: 438/780
• CPC Class Codes: B05D 1/62 Plasma-deposition of organic layers plasma deposition in general C23C14/00, C23C16/00
• CPC Class Codes: G03F 7/167 from the gas phase, by plasma deposition G03F7/2035 takes precedence
• CPC Class Codes: H01L 21/02118 carbon based polymeric organic or inorganic material, e.g. polyimides, poly cyclobutene or PVC polymers per se C08G, photoresist per se G03F
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0332 characterised by their composition, e.g. multilayer masks, materials
• CPC Class Codes: H01L 21/3127 Layers comprising fluoro (hydro)carbon compounds, e.g. polytetrafluoroethylene
• CPC Class Codes: H01L 21/3146 Carbon layers, e.g. diamond-like layers

Abstract

A method of forming a hydrocarbon-containing polymer film on a semiconductor substrate by a capacitively-coupled plasma CVD apparatus. The method includes the steps of: vaporizing a hydrocarbon-containing liquid monomer (C_αH_βX_γ, wherein α and β are natural numbers of 5 or more; γ is an integer including zero; X is O, N or F) having a boiling point of about 20° C. to about 350° C. which is not substituted by a vinyl group or an acetylene group; introducing the vaporized gas into a CVD reaction chamber inside which a substrate is placed; and forming a hydrocarbon-containing polymer film on the substrate by plasma polymerization of the gas.

Claims

1. A method of forming a hydrocarbon-based polymer film on a semiconductor substrate by a capacitively-coupled plasma CVD apparatus, which comprises the steps of:

vaporizing a hydrocarbon-based liquid monomer (C_α

H_β

X_γ

, wherein α and

β

are natural numbers of 5 or more;

γ

is an integer including zero;

X is O, N or F) having a boiling point of about 20°

C. to about 350°

C. which is not substituted by a vinyl group or an acetylene group;

introducing said vaporized gas into a CVD reaction chamber inside which a substrate is placed; and

forming a hydrocarbon-based polymer film on said substrate by plasma polymerization of said gas.

2. The method according to claim 1, wherein said liquid monomer is a cyclic hydrocarbon.

3. The method according to claim 2, wherein said cyclic hydrocarbon is a substituted or non-substituted benzene.

4. The method according to claim 3, wherein said substituted or non-substituted benzene is C₆H₆₋

nR_n (wherein n is 0, 1, 2, or

     3);

R is independently —

CH3 or —

C2H5.

5. The method according to claim 4, wherein said substituted benzene is any one of 1,3,5-trimethylbenzene, o-xylene, m-xylene or p-xylene.

6. The method according to claim 1, wherein said liquid monomer is a linear hydrocarbon.

7. The method according to claim 1, wherein said liquid monomer is a hydrocarbon wherein γ

is equal to zero.

8. The method according to claim 1, wherein only said liquid monomer is used as a reaction gas.

9. The method according to claim 1, wherein said liquid monomer is introduced into a heater disposed upstream of said reaction chamber and vaporized.

10. The method according to claim 9, wherein said liquid monomer is flow-controlled upstream of said heater by a valve, and its introduction into said heater is blocked, except when a film is being formed, by a shutoff valve disposed between said flow control valve and said heater and kept approximately at 80°

C. or lower or at a temperature which is at least approximately 50°

C. lower than that of vaporization by heat.

11. The method according to claim 9, wherein said liquid monomer is flow-controlled by a valve, which is disposed upstream of said heater and kept at approximately 80°

C. or lower or at a temperature which is at least approximately 50°

C. lower than that of vaporization by heat, and its introduction into said heater is blocked except when a film is being formed.

12. The method according to claim 1, further comprising introducing an inert gas into the reaction chamber prior to the plasma polymerization.

13. The method according to claim 1, wherein as an additive gas, an organic gas CnHm (wherein n is an integer of 4 or less including zero;

m is any natural number) is further introduced into the reaction chamber.

14. The method according to claim 1, wherein an additive gas, a dry gas containing N, O, or F is further introduced into the reaction chamber.

31. The method according to claim 1, wherein as a reducing gas, hydrogen, ammonia, or carbon monoxide is further introduced into the reaction chamber.

15. A method of forming a hydrocarbon-based polymer film on a semiconductor substrate by a capacitively-coupled plasma CVD apparatus, which comprises the steps of:

placing a semiconductor device substrate in a CVD reaction chamber;

vaporizing a hydrocarbon-based liquid monomer (C_α

H_β

X_γ

, wherein α and

β

are natural numbers of 5 or more;

γ

is an integer including zero;

X is O, N or F) having a boiling point of about 20°

C. to about 350°

C.;

introducing said vaporized gas into the CVD reaction chamber inside which the substrate is placed; and

forming a hard mask comprising a hydrocarbon-based polymer film on said substrate by plasma polymerization of said gas.

16. The method according to claim 15, wherein said liquid monomer is a cyclic hydrocarbon.

17. The method according to claim 16, wherein said cyclic hydrocarbon is a substituted or non-substituted benzene.

18. The method according to claim 15, wherein said liquid monomer is a linear hydrocarbon.

19. The method according to claim 15, wherein said liquid monomer is a hydrocarbon wherein γ

is equal to zero.

20. The method according to claim 15, wherein only said liquid monomer is used as a reaction gas.

21. The method according to claim 15, wherein said liquid monomer is introduced into a heater disposed upstream of the reaction chamber and vaporized.

22. The method according to claim 21, wherein said liquid monomer is flow-controlled upstream of said heater by a valve, and its introduction into said heater is blocked, except when a film is being formed, by a shutoff valve disposed between said flow control valve and said heater and kept approximately at 80°

C. or lower or at a temperature which is at least approximately 50°

C. lower than that of vaporization by heat.

23. The method according to claim 21, wherein said liquid monomer is flow-controlled by a valve, which is disposed upstream of said heater and kept at approximately at 80°

C. or lower or at a temperature which is at least approximately 50°

C. lower than that of vaporization by heat, and its introduction into said heater is blocked except when a film is being formed.

24. The method according to claim 15, further comprising introducing an inert gas into the reaction chamber prior to the plasma polymerization.

25. A method of forming a hydrocarbon-based polymer film on a semiconductor substrate by a capacitively-coupled plasma CVD apparatus, which comprises the steps of:

introducing a hydrocarbon-based liquid monomer (C_α

H_β

X_γ

, wherein α and

β

are natural numbers of 5 or more;

γ

is an integer including zero;

X is O, N or F) having a boiling point of about 20°

C. to about 350°

C. into a heater through a flow control valve and further through a shutoff valve disposed downstream of the flow control valve and kept at approximately 80°

C. or lower and thereby vaporizing the monomer;

introducing the vaporized gas into a CVD reaction chamber inside which the substrate is placed; and

forming a hydrocarbon-based polymer film on said substrate by plasma polymerization of said gas.

26. The method according to claim 25, wherein said liquid monomer is mixed with an inert gas downstream of said shutoff valve and upstream of said heater.

27. The method according to claim 25, further comprising shutting off said shutoff valve after completion of film formation, and blocking inflow of said liquid monomer into said heater.

28. The method according to claim 27, wherein after shutting off said shutoff valve, inside said heater is purged by an inert gas.

29. The method according to claim 25, wherein said liquid monomer is a cyclic hydrocarbon.

30. The method according to claim 29, wherein said cyclic hydrocarbon is a substituted or non-substituted benzene.