Method of forming a high transparent carbon film

• US 7,632,549 B2
• Filed: 05/05/2008
• Issued: 12/15/2009
• Est. Priority Date: 05/05/2008
• Status: Active Grant

• Current Assignee: ASM Japan K.K. (ASM International NV)
• Original Assignee: ASM Japan K.K. (ASM International NV)
• Inventors: Goundar, Kamal Kishore
• Primary Examiner(s): Ahmed; Shamim
• Application Number:
  US12/115,386
• Publication Number:
  US 20090274851A1
• Time in Patent Office: 589 Days
• Field of Search: 427/569, 438/780
• US Class Current: 427/569
• CPC Class Codes: B05D 1/62 Plasma-deposition of organic layers plasma deposition in general C23C14/00, C23C16/00
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C23C 16/4405 Cleaning of reactor or parts inside the reactor by using reactive gases
• CPC Class Codes: C23C 16/452 by activating reactive gas streams before their introduction into the reaction chamber, e.g. by ionisation or addition of reactive species
• CPC Class Codes: H01L 21/02115 the material being carbon, e.g. alpha-C, diamond or hydrogen doped carbon
• 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 21/3146 Carbon layers, e.g. diamond-like layers

Abstract

A method of forming a transparent hydrocarbon-based polymer film on a substrate by plasma CVD includes: introducing a main gas consisting of a hydrocarbon gas (C_αH_β, wherein α and β are natural numbers) and an inert gas at a flow ratio (R) of C_αH_β/inert gas of 0.25 or less into a CVD reaction chamber inside which a substrate is placed; and forming a hydrocarbon-based polymer film on the substrate by plasma polymerization of the gas at a processing temperature (T) wherein T≦(−800R+500).

Claims

1. A method of forming a transparent hydrocarbon-based polymer film on a substrate by plasma CVD, comprising:

introducing a main gas consisting of a hydrocarbon gas (C_α

H_β

, wherein α and

β

are natural numbers) and an inert gas at a flow ratio (R) of C_α

H_β

/inert gas of 0.25 or less into a CVD reaction chamber inside which a substrate is placed, wherein the liquid monomer has a carbon/hydrogen ratio (C/H) of 0.5 or higher and has no benzene ring; and

forming a hydrocarbon-based polymer film on the substrate by plasma polymerization of the gas at a processing temperature (T°

C.) wherein T≦

(−

800R+500) and T<

350, at a pressure of less than 1000 Pa, and at an RF power density of about 0.01 W/cm² to about 20 W/cm²,

wherein the flow ratio and the processing temperature are controlled, thereby forming the hydrocarbon-based polymer film having an extinction coefficient of 0.05 or less as measured at a lighting optical wavelength of 633 nm, a modulus of 20 GPa or higher, and a hardness of 4 GPa or higher.

2. The method according to claim 1, wherein the hydrocarbon gas is a gaseous phase of a hydrocarbon liquid monomer (C_α

H_β

, wherein α and

β

are natural numbers of 5 or more) having a boiling point of about 20°

C. to about 350°

C.

3. The method according to claim 1, wherein the processing temperature is below 400°

C.

4. The method according to claim 1, wherein the flow ratio is 0.2 or less.

5. The method according to claim 1, wherein the inert gas is Ar, He, Ne, Kr, and/or N2.

6. The method according to claim 2, wherein the liquid monomer is cyclic.

7. The method according to claim 6, wherein the liquid monomer is cyclopentane.

8. The method according to claim 6, wherein the liquid monomer is cyclopentene.

9. The method according to claim 6, wherein said liquid monomer is isoprene.

10. The method according to claim 1, wherein the step of introducing the main gas further comprises introducing as an additive gas an organic gas CnHm (wherein n is an integer of 4 or less including zero;

m is any natural number) into the reaction chamber.

11. The method according to claim 1, wherein the step of introducing the main gas further comprises introducing as an additive gas a dry gas containing any one or more or all of N, O, and F is into the reaction chamber.

12. The method according to claim 1, wherein the forming polymer film has a density of more than 1.0 g/cm³.

13. The method according to claim 1, wherein the forming polymer film has a refractive index (n) of 1.6 or higher at a lighting optical wave length of 633 nm.

14. The method according to claim 1, wherein the forming polymer film is formed on the substrate as a hard mask.