Substrate processing method

• US 8,202,805 B2
• Filed: 03/09/2010
• Issued: 06/19/2012
• Est. Priority Date: 03/13/2009
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Kushibiki, Masato, Nishimura, Eiichi
• Primary Examiner(s): Picardat, Kevin M
• Assistant Examiner(s): PRASAD, NEIL R
• Application Number:
  US12/720,197
• Publication Number:
  US 20100233885A1
• Time in Patent Office: 833 Days
• Field of Search: 438/313, 438/778, 438/780, 438/781, 438/790
• US Class Current: 438/771
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32779 of batches of workpieces
• CPC Class Codes: H01L 21/0273 characterised by the treatment of photoresist layers
• CPC Class Codes: H01L 21/0337 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/32139 using masks

Abstract

A method for processing a substrate including a processing target layer and an organic film, include: a deposition/trimming process of forming a reinforcement film on a surface of the organic film and, at the same time, trimming a line width of a line portion of the organic film constituting an opening pattern. The deposition/trimming process includes an adsorption process for allowing a silicon-containing gas to be adsorbed onto the surface of the organic film and an oxidation process in which the line width of the organic film is trimmed while the adsorbed silicon-containing gas is converted into a silicon oxide film. A monovalent aminosilane is employed as the silicon-containing gas.

Claims

1. A method for processing a substrate including a processing target layer and an organic film, the method comprising:

a deposition/trimming process of forming a reinforcement film on a surface of the organic film and, at the same time, trimming a line width of a line portion of the organic film constituting an opening pattern,

wherein the deposition/trimming process includes an adsorption process for allowing a silicon-containing gas to be adsorbed onto the surface of the organic film; and

an oxidation process in which the line width of the organic film is trimmed while the adsorbed silicon-containing gas is converted into a silicon oxide film serving as the reinforcement film.

2. The method of claim 1, wherein a monovalent aminosilane is employed as the silicon-containing gas.

3. The method of claim 1, wherein, in the adsorption process, a processing pressure is in the range from approximately 1.33×

10<sup>−

1</sup> Pa (1 mTorr) to 1.33×

10 kPa(100 Torr).

4. The method of claim 1, wherein, in the adsorption process, a processing temperature is in a range from approximately 20°

C. to 700°

C.

5. The method of claim 1, wherein, in the oxidation process, the line width of the organic film is trimmed and, at the same time, the silicon-containing gas adsorbed onto the surface of the organic film is converted into the silicon oxide film by oxygen radicals generated by plasma-exciting an oxygen-containing gas serving as an oxidizing gas.

6. The method of claim 1, wherein, in the oxidation process, a processing pressure is in the range from approximately 1.33×

10<sup>−

1</sup> Pa (1 mTorr) to 1.33×

10 kPa(100 Torr).

7. The method of claim 1, wherein, in the oxidation process, a processing temperature is in the range from approximately 20°

C. to 700°

C.

8. The method of claim 1, wherein the line width of the line portion of the organic film is equal to or smaller than approximately 60 nm.

9. The method of claim 1, further comprising a reinforcement film etching process of partially etching the reinforcement film formed in the deposition/trimming process to expose the trimmed line portion of the organic film.

10. The method of claim 1, further comprising repeating the deposition/trimming process until a required mask layer is obtained, wherein the reinforcement film obtained by the repetition of the deposition/trimming process serves as the mask layer.

11. The method of claim 2, wherein, in the adsorption process, a processing pressure is in the range from approximately 1.33×

10<sup>−

1</sup> Pa(1 mTorr) to 1.33×

10 kPa(100 Torr).

12. The method of claim 3, wherein, in the adsorption process, a processing temperature is in a range from approximately 20°

C. to 700°

C.

13. The method of claim 6, wherein, in the oxidation process, a processing temperature is in the range from approximately 20°

C. to 700°

C.

14. The method of claim 13, wherein, the silicon-containing gas adsorbed onto the surface of the organic film is converted into the silicon oxide film by oxygen radicals generated by plasma-exciting an oxygen-containing gas serving as an oxidizing gas by applying a high frequency power ranging from 500 W to 3000 W.

15. The method of claim 11, wherein, in the adsorption process, a processing temperature is in a range from approximately 20°

C. to 700°

C.

16. The method of claim 15, wherein, in the oxidation process, a processing pressure is in the range from approximately 1.33×

10<sup>−

1</sup> Pa(1 mTorr) to 1.33×

10 kPa(100 Torr).

17. The method of claim 16, wherein, in the oxidation process, a processing temperature is in the range from approximately 20°

C. to 700°

C.

18. The method of claim 17, wherein, the silicon-containing gas adsorbed onto the surface of the organic film is converted into the silicon oxide film by oxygen radicals generated by plasma-exciting an oxygen-containing gas serving as an oxidizing gas by applying a high frequency power ranging from 500 W to 3000 W.