Reflective mask blank, reflective mask and method of manufacturing semiconductor device

• US 10,642,149 B2
• Filed: 07/05/2019
• Issued: 05/05/2020
• Est. Priority Date: 12/24/2014
• Status: Active Grant

• Current Assignee: Hoya Corporation
• Original Assignee: Hoya Corporation
• Inventors: Hamamoto, Kazuhiro, Ikebe, Yohei
• Primary Examiner(s): Young, Christopher G
• Application Number:
  US16/504,151
• Publication Number:
  US 20190339608A1
• Time in Patent Office: 305 Days
• Field of Search: 430 5
• CPC Class Codes: C03C 15/00 Surface treatment of glass, not in the form of fibres or filaments, by etching etching or surface-brightening compositions, in general C09K13/00
• CPC Class Codes: C03C 17/3435 comprising a nitride, oxynitride, boronitride or carbonitride
• CPC Class Codes: C03C 17/3441 comprising carbon, a carbide or oxycarbide
• CPC Class Codes: C03C 17/3636 one layer at least containing silicon, hydrogenated silicon or a silicide
• CPC Class Codes: C03C 2204/08 Glass having a rough surface
• CPC Class Codes: C03C 23/0075 Cleaning of glass specially adapted to plate glass B08B11/00
• CPC Class Codes: C03C 3/06 with more than 90% silica by weight, e.g. quartz C03C3/045 takes precedence
• CPC Class Codes: G03F 1/24 Reflection masks; Preparation thereof
• CPC Class Codes: G03F 1/32 Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof
• CPC Class Codes: G03F 1/48 Protective coatings

Abstract

A reflective mask blank capable of obtaining high contrast at the edges of a phase shift film pattern. Provided is a reflective mask blank comprising a multilayer reflective film and a phase shift film that shifts the phase of EUV light formed in that order on a substrate, wherein root mean square roughness (Rms), obtained by measuring a 1 μm×1 μm region on the surface of the phase shift film with an atomic force microscope, is not more than 0.50 nm, and power spectrum density at a spatial frequency of 10 to 100 μm⁻¹ is not more than 17 nm⁴.

Claims

1. A reflective mask blank comprising:

a substrate;

a multilayer reflective film on the substrate; and

a phase shift film that shifts a phase of extreme ultra violet (EUV) light on the multilayer reflective film;

wherein,

root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the phase shift film with an atomic force microscope, is not more than 0.50 nm, and an integrated value of power spectrum density at a spatial frequency of 10 to 100 μ

m⁻

is not more than 360 nm³.

2. The reflective mask blank according to claim 1, wherein the integrated value of power spectrum density is not more than 250 nm³.

3. The reflective mask blank according to claim 1, wherein the reflective mask further comprises a protective film on the multilayer reflective film.

4. The reflective mask blank according to claim 1, wherein an uppermost layer of the phase shift film is at least one layer selected from a group of a tantalum-based material layer, a chromium-based material layer and ruthenium-based material layer.

5. The reflective mask blank according to claim 1, wherein the reflective mask blank further comprises an etching mask film arranged in contact with the surface of the phase shift film on the opposite side from the substrate.

6. A reflective mask comprising:

a substrate;

a multilayer reflective film on the substrate; and

a phase shift film pattern that shifts a phase of extreme ultra violet (EUV) light on the multilayer reflective film;

wherein,

root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the phase shift film pattern with an atomic force microscope, is not more than 0.50 nm, and an integrated value of power spectrum density at a spatial frequency of 10 to 100 μ

m⁻

is not more than 360 nm³.

7. The reflective mask according to claim 6, wherein an uppermost layer of a phase shift film pattern is at least one layer selected from a group of a tantalum-based material layer, a chromium-based material layer and ruthenium-based material layer.

8. The reflective mask according to claim 6, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the multilayer reflective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

9. The reflective mask according to claim 8, wherein the integrated value of power spectrum density is not more than 250 nm³.

10. The reflective mask according to claim 8, the reflective mask further comprises a protective film on the multilayer reflective film.

11. The reflective mask according to claim 8, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the multilayer reflective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

12. The reflective mask according to claim 10, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the protective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

13. The reflective mask according to claim 8, wherein an uppermost layer of the phase shift film pattern is at least one layer selected from a group of a tantalum-based material layer, a chromium-based material layer and ruthenium-based material layer.

14. A method of manufacturing a semiconductor device comprising:

carrying out a lithography process with an exposure device using a reflective mask to form a transfer pattern on a transferred substrate, the reflective mask comprising;

a reflective mask substrate;

a multilayer reflective film on the reflective mask substrate; and

a phase shift film pattern that shifts a phase of extreme ultra violet (EUV) light formed on the multilayer reflective film;

wherein,

root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the phase shift film pattern with an atomic force microscope, is not more than 0.50 nm, and an integrated value of power spectrum density at a spatial frequency of 10 to 100 μ

m⁻

is not more than 360 nm³.

15. The method according to claim 14, wherein the integrated value of power spectrum density is not more than 250 nm³.

16. The method according to claim 14, wherein the reflective mask further comprises a protective film on the multilayer reflective film.

17. The method according to claim 14, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the multilayer reflective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

18. The method according to claim 16, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the protective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

19. The method according to claim 18, wherein root mean square roughness (Rms), obtained by measuring a 1 μ

m×

1 μ

m region on a surface of the multilayer reflective film with an atomic force microscope, is not more than 0.15 nm, and power spectrum density at a spatial frequency of 10 to 100 μ

m<sup>−

1</sup> is not more than 7 nm⁴.

20. The method according to claim 14, wherein an uppermost layer of the phase shift film pattern is at least one layer selected from a group of a tantalum-based material layer, a chromium-based material layer and ruthenium-based material layer.