Methods of manufacturing a lithography template

• US 7,037,639 B2
• Filed: 05/01/2002
• Issued: 05/02/2006
• Est. Priority Date: 05/01/2002
• Status: Expired due to Fees

• Current Assignee: Mii Newco, Inc.
• Original Assignee: Molecular Imprints, Inc. (Canon Inc.)
• Inventors: Voisin, Ronald D.
• Primary Examiner(s): Duda, Kathleen
• Application Number:
  US10/136,188
• Publication Number:
  US 20030205657A1
• Time in Patent Office: 1,462 Days
• Field of Search: 430/311, 430/313, 430/316, 430/322, 430/323
• US Class Current: 430/316
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G03F 1/34 Phase-edge PSM, e.g. chromeless PSM; Preparation thereof
• CPC Class Codes: G03F 7/0002 Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping
• CPC Class Codes: G03F 7/0017 for the production of embossing, cutting or similar devices; for the production of casting means
• CPC Class Codes: G03F 7/093 characterised by antistatic means, e.g. for charge depletion

Abstract

A method for forming imprint lithography templates is described herein. The method includes forming a masking layer and a conductive layer on a substrate surface. The use of a conductive layer allows patterning of the masking layer using electron beam pattern generators. The substrate is etched using the patterned masking layer to produce a template.

Claims

1. A method of forming a lithography template, the method comprising:

forming a conductive polysilicon layer upon a substrate, wherein the substrate is composed of a light transmissive material;

forming a masking layer upon the conductive polysilicon layer;

forming a pattern in the masking layer such that a portion of the conductive polysilicon layer is exposed through the masking layer;

etching one or more of the exposed portions of the conductive polysilicon layer such that a portion of the substrate is exposed through the conductive polysilicon layer; and

etching one or more of the exposed portions of the substrate.

2. The method of claim 1, further comprising removing the masking layer and the conductive polysilicon layer, providing the substrate formed from a material selected from a set of materials consisting essentially of glass, quartz glass and fused silica, with said conductive polysilicon layer being n-doped polysilicon.

3. The method of claim 1 wherein the conductive polysilicon layer has a conductivity sufficient to remove a portion of a charge from the substrate during patterning of the masking layer with an electron beam pattern generator.

4. The method of claim 1, wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to an electron beam with an electron beam pattern generator; and

removing one or more of the exposed portions of the photoresist material.

5. The method of claim 1, wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to light with a laser pattern generator; and

removing one or more of the exposed portions of the photoresist material.

6. The method of claim 1 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to an electron beam with an electron beam pattern generator; and

removing one or more of the unexposed portions of the photoresist material.

7. The method of claim 1 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to light with a laser pattern generator; and

removing one or more of the unexposed portions of the photoresist material.

8. The method of forming alithography template, the method comprising:

providing a substrate, the substrate comprising a base layer, an etch stop layer disposed upon the base layer, and an upper layer disposed above the etch stop layer, wherein the base layer, the etch stop layer, and the upper layer are composed of a light transmissive material;

forming a conductive polysilicon layer upon the upper layer;

forming a masking layer upon the conductive polysilicon layer;

forming a pattern in the masking layer such that a portion of the conductive polysilicon layer is exposed through the masking layer;

etching one or more of the exposed portions of the conductive polysilicon layer such that a portion of the substrate is exposed through the polysilicon layer; and

etching one or more of the exposed portions of the substrate until the etch stop ayer is reached.

9. The method of claim 8 wherein providing said substrate further includes providing the substrate formed from a material selected from a set of materials consisting essentially of glass, quartz glass and fused silica, forming said etch stop layer from indium tin oxide, and forming said upper layer from materials selected from a set consisting essentially of deposited silicon dioxide and grown quartz and said forming said conductive polysilicon layer further including forming said conductive polysilicon layer from n-doped polysilicon.

10. The method of claim 8 wherein the conductive polysilicon layer has a conductivity sufficient to remove a portion of a charge from the substrate during etching of the masking layer with an electron beam pattern generator.

11. The method of claim 8 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to an electron beam with an electron beam pattern generator; and

removing one or more of the exposed portions of the photoresist material.

12. The method of claim 8 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to light with a laser pattern generator; and

removing one or more of the exposed portions of the photoresist material.

13. The method of claim 8 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to an electron beam with an electron beam pattern generator; and

removing one or more of the unexposed portions of the photoresist material.

14. The method of claim 8 wherein the masking layer is a photoresist material, and wherein forming the pattern in the masking layer comprises:

coating the conductive polysilicon layer with the photoresist material;

exposing one or more portions of the photoresist material to light with a laser pattern generator; and

removing one or more of the unexposed portions of the photoresist material.

15. The method of claim 8 wherein the depth of the pattern etched in the substrate is selected for a desired aspect ratio in the template and wherein inspecting the pattern formed on the conductive polysilicon layer comprises exposing the conductive polysilicon layer to an inspection light, wherein a thickness of the conductive polysilicon layer and the wavelength of the inspection light are predetermined to enhance a contrast between the patterned conductive polysilicon layer and the exposed portions of the substrate.

16. The method of claim 8 wherein said conductive polysilicon layer has a thickness that is about ½

of a wavelength of an inspection light.

17. A method of patterning a lithographic template, said method comprising:

forming, on said lithographic template, a layer of conductive polysilicon material that is transparent to visible light;

applying, on said layer of conductive polysilicon material, a masking layer;

creating a pattern in said masking layer to expose a sub-portion of said layer of conductive polysilicon material; and

transferring said pattern into said template.

18. The method as recited in claim 17 wherein said polysilicon material is selected from a set consisting of titanium silicide, tungsten silicide and cobalt silicide.

19. The method as recited in claim 17 wherein forming further includes depositing said layer of conductive polysilicon material employing chemical vapor deposition techniques.

20. The method as recited in claim 17 wherein forming further includes implanting ions into said layer of conductive polysilicon layer.

21. The method as recited in claim 20 wherein said ions are selected from a set of ions consisting of phosphorous, boron and arsenic.

22. The method as recited in claim 20 further includes annealing said layer of conductive polysilicon material.