Mask blank, mask blank with negative resist film, phase shift mask, and method for producing pattern formed body using same

Patent metadata

Field	Value
Publication number	US-9874808-B2
Application number	US-201414912831-A
Country	US
Kind code	B2
Filing date	Aug 21, 2014
Priority date	Aug 21, 2013
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

The present invention provides a mask blank used to produce a halftone phase shift mask to which ArF excimer laser exposure light is to be applied. The present invention attains the object by providing the mask blank comprising a transparent substrate, and a light semitransmissive layer formed on the transparent substrate and made only of Si and N or a light semitransmissive layer formed on the transparent substrate and made only of Si, N and O, wherein the light semitransmissive layer has an extinction coefficient of 0.2 to 0.45 at a wavelength of ArF excimer laser exposure light, a refractive index of 2.3 to 2.7 at the wavelength of ArF excimer laser exposure light, and a transmittance of 15 to 38% at the wavelength of ArF excimer laser exposure light, and further has a layer thickness of 57 to 67 nm.

First claim

The invention claimed is:

1. A mask blank used to produce a halftone phase shift mask to which ArF excimer laser exposure light is to be applied,
the mask blank comprises a transparent substrate, and a light semitransmissive layer formed on the transparent substrate and made only of Si and N or a light semitransmissive layer formed on the transparent substrate and made only of Si, N and O,
wherein the light semitransmissive layer has an extinction coefficient of 0.2 to 0.45 at a wavelength of ArF excimer laser exposure light, a refractive index of 2.3 to 2.7 at the wavelength of ArF excimer laser exposure light, and a transmittance of 15% to 38% at the wavelength of ArF excimer laser exposure light, and further has a layer thickness of 57 nm to 67 nm.

2. The mask blank according to claim 1 , wherein the light semitransmissive layer is formed directly on the transparent substrate.

3. The mask blank according to claim 1 , further comprising a light-shielding layer formed on the light semitransmissive layer, an optical density (OD value) of this light-shielding layer at the wavelength of ArF excimer laser exposure light being adjusted to be in total to a desired optical density (OD value) when combined with an optical density (OD value) of the light semitransmissive layer.

4. The mask blank according to claim 3 , wherein the light-shielding layer has a monolayered structure comprising a light-absorbing layer formed on the light semitransmissive layer and having an etching barrier function for the light semitransmissive layer and a light-absorbing function of absorbing the ArF excimer laser exposure light.

5. The mask blank according to claim 3 , wherein the light-shielding layer has a bilayered structure comprising: a light-absorbing layer formed on the light semitransmissive layer and having an etching barrier function for the light semitransmissive layer and a light-absorbing function of absorbing the ArF excimer laser exposure light; and a hard mask layer formed on the light-absorbing layer and having an etching barrier function for the light-absorbing layer.

6. The mask blank according to claim 3 , wherein the light-shielding layer has a trilayered structure comprising: an etching barrier layer formed on the light semitransmissive layer and having an etching barrier function for the light semitransmissive layer; a light-absorbing layer formed on the etching barrier layer and having a light-absorbing function of absorbing the ArF excimer laser exposure light; and a hard mask layer formed on the light-absorbing layer and having an etching barrier function for the light-absorbing layer.

7. The mask blank according to claim 6 , wherein the light-absorbing layer comprises simple silicon (Si).

8. The mask blank according to claim 3 , wherein the light-shielding layer has the optical density (OD value) at the wavelength of ArF excimer laser exposure light adjusted to be in total into a value of 3.0 or more when combined with the optical density (OD value) of the light semitransmissive layer.

9. A negative-type resist layer attached mask blank, comprising the mask blank recited in claim 1 , and a negative-type resist layer formed on the mask blank.

10. A method for producing a pattern formed body, using a phase shift mask made from the mask blank recited in claim 1 ,
comprising a step of using the phase shift mask to form a resist pattern by negative tone development.

11. A halftone phase shift mask to which ArF excimer laser exposure light is to be applied,
the mask comprising a transparent substrate, and a light semitransmissive layer pattern formed on the transparent substrate and made only of Si and N or a light semitransmissive layer pattern formed on the transparent substrate and made only of Si, N and O,
wherein the light semitransmissive layer pattern has an extinction coefficient of 0.2 to 0.45 at a wavelength of ArF excimer laser exposure light, a refractive index of 2.3 to 2.7 at the wavelength of ArF excimer laser exposure light, and a transmittance of 15% to 38% at the wavelength of ArF excimer laser exposure light, and further has a layer thickness of 57 nm to 67 nm.

12. The phase shift mask according to claim 11 , wherein the light semitransmissive layer pattern comprises a convex pattern-element having a width or length of 60 nm or less.

13. The phase shift mask according to claim 11 , wherein: the light semitransmissive layer pattern has a main pattern which is to be resolved onto a wafer, and an assistant pattern which is used to assist the resolution of the main pattern and is not to be resolved onto the wafer; and the assistant pattern comprises one or more convex pattern-elements each having a width or length of 60 nm or less.

14. The phase shift mask according to claim 11 , wherein the light semitransmissive layer pattern is formed directly on the transparent substrate.

15. The phase shift mask according to claim 11 , which is a negative-type phase shift mask.

16. The phase shift mask according to claim 11 , further comprising a light-shielding layer pattern formed on the light semitransmissive layer pattern, an optical density (OD value) of this light-shielding layer pattern at the wavelength of ArF excimer laser exposure light being adjusted to be in total into a desired value (OD value) when combined with an optical density of the light semitransmissive layer pattern.

17. The phase shift mask according to claim 16 , wherein the light-shielding layer pattern has a monolayered structure comprising a light-absorbing layer pattern formed on the light semitransmissive layer pattern and having an etching barrier function for the light semitransmissive layer pattern and a light-absorbing function of absorbing the ArF excimer laser exposure light.

18. The phase shift mask according to claim 16 , wherein the light-shielding layer pattern has a bilayered structure comprising: an etching barrier layer pattern formed on the light semitransmissive layer pattern and having an etching barrier function for the light semitransmissive layer pattern; and a light-absorbing layer pattern formed on the etching barrier layer pattern and having a light-absorbing function of absorbing the ArF excimer laser exposure light.

19. The phase shift mask according to claim 18 , wherein the light-absorbing layer pattern comprises simple silicon (Si).

20. The phase shift mask according to according to claim 16 , wherein the light-shielding layer pattern has the optical density (OD value) at the wavelength of ArF excimer laser exposure light adjusted to be in total into a value of 3.0 or more when combined with the optical density of the light semitransmissive layer pattern.

Assignees

• Dainippon Printing Co Ltd

Inventors

• Adachi Takashi
• Miura Youichi
• Takamizawa Hideyoshi
• Hayano Katsuya
• Ohkawa Youhei
• Watanabe Hiroshi
• Tani Ayako

Classifications

• G03F1/32 Primary

  Attenuating PSM [att-PSM], e.g. halftone PSM or PSM having semi-transparent phase shift portion,; Preparation thereof · CPC title

• G03F7/32

  Liquid compositions therefor, e.g. developers · CPC title

• G03F1/26

  Phase shift masks [PSM]; PSM blanks; Preparation thereof · CPC title

• G03F1/20

  Masks or mask blanks for imaging by charged particle beam [CPB] radiation, e.g. by electron beam; Preparation thereof · CPC title

• H10P76/4085

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