METHOD FOR DEPOSITING AN AMORPHOUS CARBON FILM WITH IMPROVED DENSITY AND STEP COVERAGE

• US 20080153311A1
• Filed: 03/05/2008
• Published: 06/26/2008
• Est. Priority Date: 06/28/2006
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ha, Hyoung-Chan, Janakiraman, Karthik, Rathi, Sudha, Padhi, Deenesh, Seamons, Martin Jay, Witty, Derek R., Park, Sohyun, Chan, Chiu, Balasubramanian, Ganesh, Kim, Bok Hoen, Sivaramakrishnan, Visweswaren, M'Saad, Hichem
• Application Number:
  US12/042,829
• Publication Number:
  US 20080153311A1
• Time in Patent Office: Days
• US Class Current: 438/780
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C23C 16/5096 Flat-bed apparatus
• CPC Class Codes: C23C 16/56 After-treatment
• 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
• CPC Class Codes: H01L 21/3146 Carbon layers, e.g. diamond-like layers

Abstract

A method for depositing an amorphous carbon layer on a substrate includes the steps of positioning a substrate in a chamber, introducing a hydrocarbon source into the processing chamber, introducing a heavy noble gas into the processing chamber, and generating a plasma in the processing chamber. The heavy noble gas is selected from the group consisting of argon, krypton, xenon, and combinations thereof and the molar flow rate of the noble gas is greater than the molar flow rate of the hydrocarbon source. A post-deposition termination step may be included, wherein the flow of the hydrocarbon source and the noble gas is stopped and a plasma is maintained in the chamber for a period of time to remove particles therefrom.

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 into the processing chamber;

introducing a noble gas from the group consisting of argon, krypton, xenon, helium, and combinations thereof into the processing chamber, wherein the molar flow rate of the noble gas is greater than the molar flow rate of the hydrocarbon source;

generating a plasma in the processing chamber; and

forming an amorphous carbon layer on the substrate, wherein the amorphous carbon layer has a density between about 1.8 g/cc and about 2.5 g/cc.

2. The method of claim 1, wherein the molar flow rate of the noble gas is about 2 to 40 times greater than the molar flow rate of the hydrocarbon source.

3. The method of claim 2, wherein the noble gas is argon.

4. The method of claim 1, further comprising:

stopping the flow of the hydrocarbon source into the processing chamber; and

flowing a plasma-maintaining gas into the processing chamber to maintain a plasma therein.

5. The method of claim 4, wherein the plasma-maintaining gas is helium and wherein flowing helium into the processing chamber continues for about 5 to 20 seconds after stopping the flow of the hydrocarbon source into the processing chamber.

6. The method of claim 4, wherein flowing a plasma-maintaining gas into the processing chamber further comprises flowing hydrogen gas into the processing chamber.

7. The method of claim 6, wherein the ratio of the molar flow rate of the plasma-maintaining gas to the molar flow rate of the hydrogen gas is between about 1:

1 to 3;

1.

8. The method of claim 1, wherein the hydrocarbon source is selected from the group consisting of aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and combinations thereof.

9. The method of claim 1, wherein the substrate processing chamber is a capacitively coupled plasma-enhanced CVD chamber.

10. The method of claim 9, wherein the pressure in the substrate processing chamber is about 1 Torr to 10 Torr during the process of forming an amorphous carbon layer on the substrate.

11. The method of claim 1, wherein the amorphous carbon layer is formed to have an extinction coefficient in the visible spectrum that is no greater than about 0.8.

12. The method of claim 11, further comprising heating the substrate to a temperature of no more than about 800°

C. during the process of forming an amorphous carbon layer on the substrate.

23. The method of claim 1, wherein the hydrocarbon source is selected from the group consisting of ethylene, propylene, acetylene, and toluene.

24. The method of claim 6, wherein the ratio of the molar flow rate of the hydrogen gas to the molar flow rate of the hydrocarbon source is between about 0 and about 20.

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

positioning a substrate in a substrate processing chamber;

introducing a hydrocarbon source into the processing chamber;

introducing a diluent gas for the hydrocarbon source into the processing chamber, wherein the molar flow rate of the diluent gas is about 2 to 40 times the molar flow rate of the hydrocarbon source;

generating a plasma in the processing chamber; and

forming an amorphous carbon layer on the substrate, wherein the density of the amorphous carbon layer is between about 1.8 g/cc and about 2.5 g/cc.

14. The method of claim 13, wherein the diluent gas is helium.

15. The method of claim 13, wherein the diluent gas is argon.

16. The method of claim 13, further comprising:

stopping the flow of the hydrocarbon source into the processing chamber; and

flowing a plasma-maintaining gas into the processing chamber to maintain a plasma therein.

17. The method of claim 16, wherein flowing a plasma-maintaining gas into the processing chamber further comprises flowing hydrogen gas into the processing chamber.

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

positioning a substrate in a substrate processing chamber;

introducing a hydrocarbon source into the processing chamber;

introducing argon into the processing chamber as a diluent of the hydrocarbon source;

generating a plasma in the processing chamber;

maintaining a pressure of about 1 Torr to 10 Torr in the processing chamber after initiating plasma therein; and

forming an amorphous carbon layer on the substrate, wherein the amorphous carbon layer has a density between about 1.8 g/cc and about 2.5 g/cc.

19. The method of claim 18, wherein the molar flow rate of argon is about 2 to 40 times the molar flow rate of the hydrocarbon source.

20. The method of claim 19, wherein the amorphous carbon layer is formed to have an extinction coefficient in the visible spectrum no greater than about 0.8.

21. The method of claim 18, further comprising introducing hydrogen gas into the processing chamber.

22. The method of claim 21, wherein the ratio of the molar flow rate of the argon to the molar flow rate of the hydrogen is about 2:

1 to 4;

1.