Selective deposition of carbon on photoresist layer for lithography applications

Patent metadata

Field	Value
Publication number	US-12249509-B2
Application number	US-202318228234-A
Country	US
Kind code	B2
Filing date	Jul 31, 2023
Priority date	May 12, 2020
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

A method for etching a hardmask layer includes forming a photoresist layer comprising an organometallic material on a hardmask layer comprising a metal-containing material, exposing the photoresist layer to ultraviolet radiation through a mask having a selected pattern, removing un-irradiated areas of the photoresist layer to pattern the photoresist layer, forming a passivation layer comprising a carbon-containing material selectively on a top surface of the patterned photoresist layer, and etching the hardmask layer exposed by the patterned photoresist layer having the passivation layer formed thereon.

First claim

What is claimed is:

1. A method for etching a hardmask layer, comprising:
forming a patterned photoresist layer having openings on a hardmask layer;
forming a passivation layer comprising a carbon-containing material only on a top surface of the patterned photoresist layer; and
etching portions of the hardmask layer exposed by the openings of the patterned photoresist layer having the passivation layer formed thereon.

2. The method of claim 1 , wherein the patterned photoresist layer has a thickness of between 1 nm and 1 μm, and the openings have critical dimensions of between 14 nm and 22 nm.

3. The method of claim 1 , wherein the patterned photoresist layer comprises an extreme ultraviolet (EUV) sensitive photo resist.

4. The method of claim 1 , wherein the forming of the passivation layer comprises:
supplying deposition gas comprising a gas selected from the group consisting of CO and CH 4 onto the patterned photoresist layer.

5. The method of claim 1 , wherein the hardmask layer comprises tin oxide (SnO), tin silicon oxide (SnSiO), tantalum oxide (TaO), indium tin oxide (InSnO), indium gallium zinc oxide (IGZO), one or more alloys thereof, one or more dopants thereof, or any combination thereof.

6. A method for etching a film stack, comprising:
forming a bottom anti-reflective coating layer on a film stack;
forming a hardmask layer comprising a metal-containing material on the bottom anti-reflective coating layer;
forming a patterned photoresist layer having openings on the hardmask layer;
forming a passivation layer comprising a carbon-containing material only on a top surface of the patterned photoresist layer;
etching portions of the hardmask layer exposed by the openings of the patterned photoresist layer having the passivation layer formed thereon;
etching the bottom anti-reflective coating layer exposed by the patterned hardmask layer to pattern the bottom anti-reflective coating layer; and
etching the film stack exposed by the patterned bottom anti-reflective coating layer.

7. The method of claim 6 , wherein the patterned photoresist layer has a thickness of between 1 nm and 1 μm, and the openings have critical dimensions of between 14 nm and 22 nm.

8. The method of claim 6 , wherein the patterned photoresist layer comprises organometallic material comprising one or more metal elements and organic ligands.

9. The method of claim 8 , wherein the one or more metal elements comprise tin (Sn).

10. The method of claim 6 , wherein the forming of the passivation layer comprises:
supplying deposition gas comprising a gas selected from the group consisting of CO and CH 4 onto the patterned photoresist layer.

11. The method of claim 6 , wherein the metal-containing material of the hardmask layer comprises tin (Sn).

12. The method of claim 11 , wherein the metal-containing material of the hardmask layer is selected from the group consisting of tin oxide (SnO), tin silicon oxide (SnSiO), indium tin oxide (InSnO), and any combination thereof.

13. The method of claim 6 , wherein the bottom anti-reflective coating layer comprises a carbon-containing material.

14. A method for selectively forming a passivation layer on a patterned photoresist layer, comprising:
forming a patterned photoresist layer having openings; and
forming a passivation layer comprising a carbon-containing material only on a top surface of the patterned photoresist layer.

15. The method of claim 14 , wherein the patterned photoresist layer has a thickness of between 1 nm and 1 μm, and the openings have critical dimensions of between 14 nm and 22 nm.

16. The method of claim 14 , wherein the patterned photoresist layer comprises organometallic material comprising one or more metal elements and organic ligands.

17. The method of claim 16 , wherein the one or more metal elements comprise tin (Sn).

18. The method of claim 16 , wherein the one or more metal elements are selected from the group consisting of tin (Sn), antimony (Sb), and indium (In), and any combination thereof.

19. The method of claim 14 , further comprising:
heating the patterned photoresist layer.

20. The method of claim 14 , wherein the forming of the passivation layer comprises:
supplying deposition gas comprising a gas selected from the group consisting of CO and CH 4 onto the patterned photoresist layer.

Assignees

• Applied Materials Inc

Inventors

• Gao Larry
• Fung Nancy

Classifications

• H10P50/73

  using masks for insulating materials · CPC title

• H10P76/4085 Primary

  characterised by the processes involved to create the masks · CPC title

• H10P76/405

  characterised by their composition, e.g. multilayer masks · CPC title

• H10P76/204

  of organic photoresist masks · CPC title

• H10P76/2043

  using an anti-reflective coating · CPC title