Dual tone development with a photo-activated acid enhancement component in lithographic applications

• US 8,574,810 B2
• Filed: 12/11/2009
• Issued: 11/05/2013
• Est. Priority Date: 04/27/2009
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Fonseca, Carlos A., Somervell, Mark, Scheer, Steven, Printz, Wallace P.
• Primary Examiner(s): CHU, JOHN S Y
• Application Number:
  US12/636,211
• Publication Number:
  US 20100273107A1
• Time in Patent Office: 1,425 Days
• Field of Search: 430/394, 430/270.1, 430/330
• US Class Current: 430/270.1
• CPC Class Codes: G03F 7/0045 with organic non-macromolecular light-sensitive compounds not otherwise provided for, e.g. dissolution inhibitors
• CPC Class Codes: G03F 7/0392 the macromolecular compound being present in a chemically amplified positive photoresist composition
• CPC Class Codes: G03F 7/2024 of the already developed image
• CPC Class Codes: G03F 7/322 Aqueous alkaline compositions
• CPC Class Codes: G03F 7/325 Non-aqueous compositions
• CPC Class Codes: G03F 7/40 Treatment after imagewise removal, e.g. baking
• CPC Class Codes: G03F 7/70425 Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning
• CPC Class Codes: G03F 7/70466 Multiple exposures, e.g. combination of fine and coarse exposures, double patterning or multiple exposures for printing a single feature stitching G03F7/70475

Abstract

A method and system for patterning a substrate using a lithographic process, such as a dual tone development process, is described. The method comprises use of at least one photo-activated acid enhancement component to improve process latitude for the dual tone development process.

Claims

1. A method of patterning a substrate, comprising:

forming a layer of radiation-sensitive material on a substrate, said layer of radiation-sensitive material comprises two or more photo-activated acid enhancement components; and

exposing said layer of radiation-sensitive material to electromagnetic (EM) radiation using a lithography exposure system including a radiation source for said EM radiation and an imaging system for projecting said EM radiation from said radiation source to said substrate, said EM radiation containing a first wavelength or first range of wavelengths, and a second wavelength or second range of wavelengths different from said first wavelength or first range of wavelengths,

wherein one of said two or more photo-activated acid enhancement components is selected to augment an acid concentration in said layer of radiation-sensitive material when exposed to said EM radiation at said first wavelength or first range of wavelengths, and

wherein another of said two or more photo-activated acid enhancement components is selected to augment said acid concentration in said layer of radiation-sensitive material when exposed to EM radiation at said second wavelength or second range of wavelengths.

2. The method of claim 1, wherein each of said two or more photo-activated acid enhancement components is selected from the group consisting of a photo-acid generator (PAG) or a photo-decomposable base (PDB).

3. The method of claim 1, wherein said two or more photo-activated acid enhancement components comprises a first photo-acid generator and a second photo-acid generator,

wherein said first photo-acid generator generates acid in said layer of radiation-sensitive material when exposed to said EM radiation at said first wavelength or first range of wavelengths, and

wherein said second photo-acid generator generates acid in said layer of radiation-sensitive material when exposed to EM radiation at a second wavelength or second range of wavelengths.

4. The method of claim 3, wherein said first photo-acid generator is formulated to generate acid at a target wavelength and generate little to no acid beyond a pre-determined cut-off wavelength, and wherein said second photo-acid generator is formulated to generate acid at another target wavelength and generate little to no acid beyond another pre-determined cut-off wavelength.

7. The method of claim 1, wherein said exposing said layer of radiation-sensitive material to electromagnetic (EM) radiation comprises exposing said layer of radiation-sensitive material to electromagnetic (EM) radiation during a patterned exposure, or a flood exposure, or both a patterned exposure and a flood exposure.

8. The method of claim 7, wherein said patterned exposure is configured for exposing said layer of radiation-sensitive material to said first wavelength or first range of wavelengths, and said flood exposure is configured for exposing said layer of radiation-sensitive material to said second wavelength or second range of wavelengths.

9. The method of claim 7, wherein said patterned exposure is performed at 193 nanometers (nm), and said flood exposure is performed at 436 nm or 365 nm.

10. The method of claim 7, wherein said flood exposure is configured for exposing said layer of radiation-sensitive material to said first wavelength or first range of wavelengths, and said second wavelength or second range of wavelengths.

11. The method of claim 7, wherein said flood exposure comprises continuous EM radiation, pulsed EM radiation, poly-chromatic EM radiation, mono-chromatic EM radiation, broad-band EM radiation, or narrow-band radiation, or a combination thereof.

12. The method of claim 7, wherein said flood exposure comprises 436 nm (nanometer) EM radiation, 365 nm EM radiation, 248 nm EM radiation, 193 nm EM radiation, 157 nm EM radiation, deep ultraviolet (DUV) EM radiation, extreme ultraviolet (EUV) EM radiation, or electron beam radiation, or any combination of two or more thereof.

13. The method of claim 7, wherein said patterned exposure comprises 365 nm EM radiation, 248 nm EM radiation, 193 nm EM radiation, 157 nm EM radiation, or 13 nm EM radiation.

20. The method of claim 1, wherein said exposing comprises:

first, exposing said layer of radiation-sensitive material to said EM radiation at said first wavelength or first range of wavelengths; and

second, exposing said layer of radiation-sensitive material to said EM radiation at said second wavelength or second range of wavelengths,

wherein said lithography exposure system includes a first exposure system including a first EM radiation source for said EM radiation at said first target wavelength and a first imaging system, and a second exposure system including a second EM radiation source for said EM radiation at said second target wavelength and a second imaging system.

5. A method of patterning a substrate, comprising:

forming a layer of radiation-sensitive material on a substrate, said layer of radiation-sensitive material comprises two or more photo-activated acid enhancement components wherein said two or more photo-activated acid enhancement components comprises a first photo-decomposable base and a second photo-decomposable base, and

exposing said layer of radiation-sensitive material to electromagnetic (EM) radiation, said EM radiation containing a first wavelength or first range of wavelengths, and a second wavelength or second range of wavelengths different from said first wavelength or first range of wavelengths,

wherein said first photo-decomposable base is selected to neutralize base in said layer of radiation-sensitive material when exposed to said EM radiation at said first wavelength or first range of wavelengths to augment an acid concentration in said layer of radiation-sensitive material, and

wherein said second photo-decomposable base is selected to neutralize base in said layer of radiation-sensitive material when exposed to EM radiation at said second wavelength or second range of wavelengths to augment said acid concentration in said layer of radiation-sensitive material.

6. The method of claim 5, wherein said first photo-decomposable base is formulated to neutralize base at a target wavelength and neutralize little to no base beyond a pre-determined cut-off wavelength, and wherein said second photo-decomposable base is formulated to neutralize base at another target wavelength and neutralize little to no base beyond another pre-determined cut-off wavelength.

14. A method of patterning a substrate, comprising:

forming a layer of radiation-sensitive material on a substrate, said layer of radiation-sensitive material comprises at least one photo-activated acid enhancement component;

performing a patterned exposure of said layer of radiation-sensitive material to first electromagnetic (EM) radiation, said first EM radiation containing a first wavelength or first range of wavelengths; and

performing a flood exposure of said layer of radiation-sensitive material to second EM radiation, said second EM radiation containing a second wavelength or second range of wavelengths comprising 436 nm (nanometer) EM radiation, 365 nm EM radiation, 248 nm EM radiation, 193 nm EM radiation, 157 nm EM radiation, deep ultraviolet (DUV) EM radiation, extreme ultraviolet (EUV) EM radiation, or electron beam radiation, or any combination of two or more thereof,

wherein said at least one photo-activated acid enhancement component is selected to augment an acid concentration in said layer of radiation-sensitive material when exposed to said second EM radiation.

15. The method of claim 14, wherein said at least one photo-activated acid enhancement component is selected from the group consisting of a photo-acid generator (PAG) or a photo-decomposable base (PDB).

16. The method of claim 14, further comprising:

performing a positive-tone developing process following said patterned exposure to form a first pattern in said layer of radiation-sensitive material, and performing a negative-tone developing process following said flood exposure to form a second pattern in said layer of radiation-sensitive material.

17. The method of claim 16, further comprising:

performing a first post-exposure bake following said patterned exposure and preceding said positive-tone developing process.

18. The method of claim 17, further comprising:

performing a second post-exposure bake following said flood exposure and preceding said negative-tone developing process.

19. A method of patterning a substrate, comprising:

forming a layer of radiation-sensitive material on a substrate, said layer of radiation-sensitive material comprises two or more photo-activated acid enhancement components;

first, exposing said layer of radiation-sensitive material to electromagnetic (EM) radiation at a first target wavelength within a first range of wavelengths, wherein one of said two or more photo-activated acid enhancement components is selected to augment an acid concentration in said layer of radiation-sensitive material when exposed to said first target wavelength and to provide little to no augmentation of said acid concentration at wavelengths outside said first range of wavelengths; and

second, exposing said layer of radiation-sensitive material to EM radiation at a second target wavelength within a second range of wavelengths different from and non-overlapping with said first range of wavelengths, wherein another of said two or more photo-activated acid enhancement components is selected to augment said acid concentration in said layer of radiation-sensitive material when exposed to said second wavelength and to provide little to no augmentation of said acid concentration at wavelengths outside said second range of wavelengths, wherein said first exposing is a patterned exposure at said first wavelength selected from 248 nanometers (nm), 193 nm, 157 nm, or 13 nm, and said second exposing is a flood exposure at said second wavelength selected from 436 nm or 365 nm.