Granted Patent B1

US 7,070,911 · App. 10/350,472 · Granted Jul 4, 2006

Abstract

Claims (35)

1. A method for reducing standing wave formation in a photoresist during manufacturing a semiconductor device comprising:

depositing a first anti-reflective coating having an extinction coefficient above a material, wherein said first anti-reflective coating comprises silicon and nitrogen, and exposing said first anti-reflective coating to a plasma environment to null effects of nitrogen poisoning on said photoresist;

depositing a second anti-reflective coating having an extinction coefficient above said first anti-reflective coating, and exposing said second anti-reflective coating to a plasma environment to null effects of nitrogen poisoning on said photoresist;

subsequent to exposing said first and second anti-reflective coatings to said plasma environments, depositing an oxide film comprising SiO 2 above said first and second anti-reflective coatings to prevent footing in said photoresist, such that said first anti-reflective coating, said second anti-reflective coating, and said oxide film reduce the formation of standing waves in a photoresist during a lithography process;

exposing said oxide film to a plasma environment to further enhance said prevention of footing; and

subsequent to exposing said oxide film to a plasma environment, forming said photoresist above said oxide film.

2. The method as described in claim 1 wherein said first anti-reflective coating has a thickness less than 600 angstroms.

3. The method as described in claim 1 wherein said second anti-reflective coating has a thickness no greater than 600 angstroms.

4. The method as described in claim 1 wherein said first anti-reflective coating has an extinction coefficient greater than said second anti-reflective coating.

5. The method as described in claim 1 wherein said second anti-reflective coating has an extinction coefficient greater than said first anti-reflective coating.

6. The method as described in claim 1 further comprising depositing a third anti-reflective coating above said second anti-reflective coating wherein said third anti-reflective coating has a thickness no greater than 600 angstroms.

7. A method for reducing standing waves in a photosensitive material during manufacturing of a semiconductor device comprising:

depositing a first anti-reflective coating having an extinction coefficient on a material, wherein said first anti-reflective coating comprises silicon and nitrogen;

exposing said first anti-reflective coating to a plasma environment to null effects of nitrogen poisoning in said photosensitive material;

depositing a second anti-reflective coating having an extinction coefficient above said first anti-reflective coating;

exposing said second anti-reflective coating to a plasma environment to null effects of nitrogen poisoning in said photosensitive material;

depositing an oxide layer comprising SiO 2 above said second anti-reflective coating, such that said first anti-reflective coating and said second anti-reflective coating reduce the formation of standing waves in a photosensitive material during a lithography process and said oxide layer reduces an occurrence of footing; and

exposing said oxide layers to a plasma environment to further enhance prevention of footing.

8. The method as described in claim 7 wherein said first anti-reflective coating has a thickness of less than 600 angstroms.

9. The method as described in claim 7 wherein said second anti-reflective coating has a thickness no greater than 600 angstroms.

10. The method as described in claim 7 further comprising:

depositing a third anti-reflective coating above said second anti-reflective coating wherein said third anti-reflective coating has a thickness no greater than 600 angstroms; and

exposing said third anti-reflective coating to plasma environment to null effects of nitrogen poisoning on said photosensitive material.

11. The method as described in claim 7 wherein said oxide layer comprises a plurality of layers.

12. The method as described in claim 7 wherein said first anti-reflective coating has an extinction coefficient greater than said second anti-reflective coating.

13. The method as described in claim 7 wherein said second anti-reflective coating has an extinction coefficient greater than said first anti-reflective coating.

14. A structure for reducing the formation of standing waves during manufacture of a semiconductor comprising:

a first plasma treated anti-reflective coating comprising silicon and nitrogen and having an extinction coefficient deposited on a material;

a second plasma treated anti-reflective coating having an extinction coefficient deposited above said first anti-reflective coating; and

a plasma treated oxide film comprising SiO 2 deposited above said second anti-reflective coating, such that said first anti-reflective coating, said second anti-reflective coating, and said oxide film reduce the formation of standing waves in a photosensitive material during a lithography process.

15. The structure as described in claim 14 wherein said first anti-reflective coating has an extinction coefficient greater than said second anti-reflective coating.

16. The structure as described in claim 14 wherein said second anti-reflective coating has an extinction coefficient greater than said first anti-reflective coating.

17. The structure as described in claim 14 further comprising:

depositing a third anti-reflective coating above said second anti-reflective coating wherein said third anti-reflective coating has a thickness no greater than 600 angstroms.

18. The structure as described in claim 14 wherein said anti-reflective coatings are deposited by low-pressure chemical vapor deposition.

Assignments (8)