Method for Depositing Conformal Amorphous Carbon Film by Plasma-Enhanced Chemical Vapor Deposition (PECVD)

• US 20100093187A1
• Filed: 10/12/2009
• Published: 04/15/2010
• Est. Priority Date: 10/14/2008
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Suzuki, Yoichi, Morii, Takashi, Pagdanganan, Cynthia, Rathi, Sudha, Padhi, Deenesh, Seamons, Martin Jay, Kim, Bok Hoen, Lee, Kwangduk Douglas
• Granted Patent: US 8,105,465 B2
• Time in Patent Office: Days
• US Class Current: 438/780
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/5096 Flat-bed apparatus
• CPC Class Codes: H01L 21/02115 the material being carbon, e.g. alpha-C, diamond or hydrogen doped carbon
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/3141 Deposition using atomic layer deposition techniques [ALD]
• CPC Class Codes: H01L 21/3146 Carbon layers, e.g. diamond-like layers

Abstract

Methods and apparatus for depositing an amorphous carbon layer on a substrate are provided. In one embodiment, a deposition process includes positioning a substrate in a substrate processing chamber, introducing a hydrocarbon source having a carbon to hydrogen atom ratio of greater than 1:2 into the processing chamber, introducing a plasma initiating gas selected from the group consisting of hydrogen, helium, argon, nitrogen, and combinations thereof into the processing chamber, with the hydrocarbon source having a volumetric flow rate to plasma initiating gas volumetric flow rate ratio of 1:2 or greater, generating a plasma in the processing chamber, and forming a conformal amorphous carbon layer on the substrate.

Claims

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

positioning a substrate in a substrate processing chamber;

introducing a hydrocarbon source having a carbon to hydrogen atom ratio greater than 1;

2 into the processing chamber;

introducing a plasma initiating gas selected from the group consisting of hydrogen, helium, argon, nitrogen, and combinations thereof into the processing chamber, with the hydrocarbon source having a volumetric flow rate to plasma initiating gas volumetric flow rate ratio of 1;

2 or greater;

generating a plasma in the processing chamber at a RF power of 1 W/cm² or less, a pressure of 2 Torr or greater, and a temperature of about 300°

C. to about 480°

C.; and

forming a conformal amorphous carbon layer on the substrate.

2. The method of claim 1, further comprising performing a purge processing step after forming the amorphous carbon layer.

3. The method of claim 2, further comprising repeating the amorphous carbon forming process step and the purge processing step from about 2 to about 50 cycles.

4. The method of claim 1, further comprising introducing a dilutant gas into the processing chamber with the hydrogen precursor, the plasma-initiating gas, or both.

5. The method of claim 1, wherein the hydrocarbon source has a carbon to hydrogen atom ratio of 2:

3 or greater and comprises one or more compounds selected from the group of acetylene, vinylacetylene, benzene, styrene, toluene, xylene, pyridine, acetophenone, phenol, furan, C₃H₂, C₅H₄, monofluorobenzene, difluorobenzenes, tetrafluorobenzenes, and hexafluorobenzene.

6. The method of claim 1, wherein the hydrocarbon gas volumetric flow rate to plasma initiating gas volumetric flow rate ratio is from about 1:

1 to about 1;

2.

7. The method of claim 1, wherein the RF power is applied from about 0.01 to about 5 W/cm².

8. The method of claim 1, wherein the pressure is from about 2 Torr to about 20 Torr.

9. The method of claim 1, wherein the RF power is provided by a dual-frequency system.

10. The method of claim 1, wherein the amorphous carbon layer has a conformality from about 30% to about 100%.

11. A method for processing a substrate in a processing chamber, comprising:

performing a deposition cycle, comprising;

forming a conformal amorphous carbon material on a surface of the substrate; and

flowing a purge process through the processing chamber; and

repeating the cycle between 2 and 50 times.

12. The method of claim 11, wherein the purge gas comprises an inert gas or a hydrocarbon source gas.

13. The method of claim 11, wherein the purge gas may be excited into a plasma.

14. The method of claim 11, wherein the ratio of pause step time to deposition step time may be from about 100:

1 to about 1;

100

15. The method of claim 11, wherein each deposition cycle may deposit between 2% and 50% of the thickness of the amorphous carbon layer.

16. The method of claim 11, wherein the forming a conformal amorphous carbon material on a surface of the substrate, comprises:

introducing a hydrocarbon source having a carbon to hydrogen atom ratio of 1;

2 or greater into the processing chamber;

introducing a plasma initiating gas selected from the group consisting of hydrogen, helium, argon, nitrogen, and combinations thereof into the processing chamber, with the hydrocarbon source having a volumetric flow rate to plasma initiating gas volumetric flow rate ratio of 1;

2 or greater;

generating a plasma in the processing chamber at a RF power of 5 W/cm² or less, a pressure of 2 Torr or greater, and a temperature of about 300°

C. to about 480°

C.

17. The method of claim 16, further comprising introducing a dilutant gas into the processing chamber with the hydrogen precursor, the plasma-initiating gas, or both.

18. The method of claim 16, wherein the hydrocarbon source has a carbon to hydrogen atom ratio of 2:

3 or greater and comprises one or more compounds selected from the group of acetylene, vinylacetylene, benzene, styrene, toluene, xylene, pyridine, acetophenone, phenol, furan, C₃H₂, C₅H₄, monofluorobenzene, difluorobenzenes, tetrafluorobenzenes, and hexafluorobenzene.

19. The method of claim 16, wherein the process includes one or more processing parameters selected from the group consisting of a hydrocarbon gas volumetric flow rate to plasma initiating gas volumetric flow rate ratio is from about 1:

1 to about 1;

2, the RF power is applied from about 0.01 to about 5 W/cm², the pressure is from about 2 Torr to about 20 Torr, and the pressure is from about 300°

C. to about 480°

C.

20. A method of forming an amorphous carbon layer on a substrate, comprising:

positioning a substrate in a substrate processing chamber;

introducing a hydrocarbon source having a carbon to hydrogen atom ratio greater than 1;

2 into the processing chamber;

introducing a plasma initiating gas selected from the group consisting of hydrogen, helium, argon, nitrogen, and combinations thereof into the processing chamber, with the hydrocarbon source having a volumetric flow rate to plasma initiating gas volumetric flow rate ratio of 1;

2 or greater, wherein the hydrocarbon source and the plasma initiating gas are introduced into the processing chamber by a gas distributor position between 400 mils and 600 mils from the substrate surface;

generating a plasma in the processing chamber at a RF power of 1 W/cm² or less and a temperature between about 0°

C. to about 100°

C.; and

forming a conformal amorphous carbon layer on the substrate.