ULTRA HIGH SELECTIVITY ASHABLE HARD MASK FILM

• US 20110287633A1
• Filed: 05/20/2010
• Published: 11/24/2011
• Est. Priority Date: 05/20/2010
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Lee, Kwangduk Douglas, Rathi, Sudha, Seamons, Martin Jay, Chan, Chiu, Lin, Michael H.
• Granted Patent: US 8,361,906 B2
• Time in Patent Office: Days
• US Class Current: 438/725
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• 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 21/31144 using masks

Abstract

A method of forming an amorphous carbon layer on a substrate in a substrate processing chamber, includes introducing a hydrocarbon source into the processing chamber, introducing argon, alone or in combination with helium, hydrogen, nitrogen, and combinations thereof, into the processing chamber, wherein the argon has a volumetric flow rate to hydrocarbon source volumetric flow rate ratio of about 10:1 to about 20:1, generating a plasma in the processing chamber at a substantially lower pressure of about 2 Torr to 10 Torr, and forming a conformal amorphous carbon layer on the substrate.

Claims

1. A method of forming an amorphous carbon layer on a substrate in a substrate processing chamber, comprising:

introducing a hydrocarbon source into the processing chamber;

introducing argon, alone or in combination with helium, hydrogen, nitrogen, and combinations thereof, into the processing chamber, wherein the argon has a volumetric flow rate to hydrocarbon source volumetric flow rate ratio of about 10;

1 to about 20;

1;

generating a plasma in the processing chamber at a substantially lower pressure of about 1 Torr to 10 Torr; and

forming a conformal amorphous carbon layer on the substrate.

2. The method of claim 1, wherein the gas combination comprises argon and hydrogen, and hydrogen has a volumetric flow rate to hydrocarbon source volumetric flow rate ratio of about 1:

1 to about 8;

1.

3. The method of claim 2, wherein the hydrogen gas has a volumetric flow rate to hydrocarbon source volumetric flow rate ratio of about 1.4:

1 to about 6;

1.

4. The method of claim 2, wherein the flow rate of argon is between about 10000 sccm and about 14000 sccm, and the flow rate of hydrogen is between about 800 sccm and about 1000 sccm.

5. The method of claim 2, wherein the amorphous carbon layer has a film density between about 1.9 g/cc and about 2.5 g/cc.

6. The method of claim 1, wherein the gases are introduced into the processing chamber by a gas distributor position between about 200 mils and about 1000 mils from a substrate surface.

7. The method of claim 1, wherein the hydrocarbon source comprises one or more hydrocarbon compounds having the general formula C_xF_y, wherein x has a range of between 1 and 20, and y has a range of between 1 and 20.

8. The method of claim 7, wherein one or more hydrocarbon compounds is selected from the group consisting of acetylene (C₂H₂), ethylene (C₂H₄), ethane (C₂H₆), propylene (C₃H₆), propyne (C₃H₄), propane (C₃H₈), butane (C₄H₁₀), butylene (C₄H₈), butadiene (C₄H₆) and combinations thereof.

9. The method of claim 1, wherein the hydrocarbon source is acetylene (C₂H₂), the gas combination includes helium, argon, and hydrogen, and the molar flow rate of acetylene:

helium;

argon;

hydrogen is in a ratio of 1;

0.5;

20;

1.4.

10. The method of claim 1, wherein the substrate is heated to a temperature of about 100°

C. to about 480°

C. during the formation of the amorphous carbon layer.

11. A method of forming a semiconductor device in a processing chamber, comprising:

forming an amorphous carbon layer on a substrate by introducing a gas mixture into the processing chamber, wherein the gas mixture comprises a hydrocarbon source, a plasma-initiating gas, and a diluent gas consisting of argon and hydrogen into the processing chamber, wherein the argon and hydrogen have a volumetric flow rate to hydrocarbon source volumetric flow rate ratio of about 20;

1.4;

1;

generating a plasma in the processing chamber to decompose the hydrocarbon source in the gas mixture to form the amorphous carbon layer on the substrate;

defining a pattern in at least one region of the amorphous carbon layer; and

transferring the pattern defined in the at least one region of the amorphous carbon layer into the substrate using the amorphous carbon layer as a mask.

12. The method of claim 11, wherein the plasma is generated in the processing chamber at a pressure of about 1 Torr to about 10 Torr.

13. The method of claim 11, wherein the flow rate of argon is between about 1000 sccm and about 20000 sccm, and wherein the flow rate of hydrogen is between about 500 sccm and about 5000 sccm.

14. The method of claim 11, wherein the amorphous carbon layer has a film density between about 1.9 g/cc and about 2.5 g/cc.

15. The method of claim 11, wherein the hydrocarbon source, the plasma initiating gas, and the diluent gas are introduced into the processing chamber by a gas distributor position between about 200 mils and about 1000 mils from a substrate surface.

16. The method of claim 11, wherein the hydrocarbon source comprises one or more hydrocarbon compounds having the general formula C_xH_y, wherein x has a range of between 1 and 20, and y has a range of between 1 and 20.

17. The method of claim 16, wherein one or more hydrocarbon compounds is selected from the group consisting of acetylene (C₂H₂), ethylene (C₂H₄), ethane (C₂H₆), propylene (C₃H₆), propyne (C₃H₄), propane (C₃H₈), butane (C₄H₁₀), butylene (C₄H₃), butadiene (C₄H₆) and combinations thereof.

18. The method of claim 11, wherein the hydrocarbon source is selected from the group consisting of alkanes methane (CH₄), ethane (C₂H₆), propane (C₃H₃), butane (C₄H₁₀) and its isomer isobutane, pentane (C₅H₁₂) and its isomers isopentane and neopentane, hexane (C₆H₁₄) and its isomers 2-methylpentance, 3-methylpentane, 2,3-dimethylbutane, and 2,2-dimethyl butane, ethylene, propylene, butylene and its isomers, pentene and its isomers, and the like, butadiene, isoprene, pentadiene, hexadiene and the like, halogenated alkenes include monofluoroethylene, difluoroethylenes, trifluoroethylene, tetrafluoroethylene, monochloroethylene, dichloroethylenes, trichloroethylene, tetrachloroethylene, and the like, acetylene (C₂H₂), propyne (C₃H₄), butylene (C₄H₈), vinylacetylene and derivatives thereof, benzene, styrene, toluene, xylene, ethylbenzene, acetophenone, methyl benzoate, phenyl acetate, phenol, cresol, furan, and the like, alpha-terpinene, cymene, 1,1,3,3,-tetramethylbutylbenzene, t-butylether, t-butylethylene, methyl-methacrylate, and t-butylfurfurylether, C₃H₂ and C₅H₄, halogenated aromatic compounds including monofluorobenzene, difluorobenzenes, tetrafluorobenzenes, hexafluorobenzene.

19. The method of claim 11, wherein the substrate is heated to a temperature of about 100°

C. to about 480°

C. during the formation of the amorphous carbon layer.

20. The method of claim 11, wherein a single frequency RF power between about 500 Watts and about 3000 Watts is applied during formation of the amorphous carbon layer.