Glass substrate for EUVL, manufacturing method thereof, mask blank for EUVL, and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-12209046-B2
Application number	US-202117245585-A
Country	US
Kind code	B2
Filing date	Apr 30, 2021
Priority date	May 13, 2020
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

A glass substrate for EUVL includes a first main surface having a rectangular shape; a second main surface having a rectangular shape on an opposite side to the first main surface; four end surfaces orthogonal to the first and second main surfaces; four first chamfered surfaces formed on boundaries between the first main surface and the end surfaces; and four second chamfered surfaces formed on boundaries between the second main surface and the end surfaces. The glass substrate for EUVL is formed of quartz glass containing TiO 2 . The end surfaces include fluorine (F) and an element (A) other than fluorine that forms a gas cluster with fluorine, and satisfy relations:

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1

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[
nm
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{

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First claim

What is claimed is:

1. A glass substrate for Extreme Ultra-Violet Lithography (EUVL) comprising:
a first main surface having a rectangular shape;
a second main surface having a rectangular shape and being on an opposite side to the first main surface;
four end surfaces being orthogonal to the first main surface and the second main surface;
four first chamfered surfaces formed on boundaries between the first main surface and the four end surfaces respectively; and
four second chamfered surfaces formed on boundaries between the second main surface and the four end surfaces respectively,
wherein the glass substrate for EUVL is formed of quartz glass containing titanium dioxide (TiO 2 ), and
wherein the end surfaces include fluorine (F) and an element (A) other than fluorine that forms a gas cluster with fluorine, and satisfy relations (1) and (2):

[

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⁢

1

]

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=

∫
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=

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[
nm
]

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x

+

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2

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

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[
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where D1(x) in the relation (1) represents an intensity of fluorine (F) normalized with an intensity of silicon (Si) measured by Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS), x represents a depth from the end surface (in units of nm), a1x+b1 represents a linear expression in terms of x obtained by approximating D1(x) using a least squares method for x which is greater than or equal to 200 and less than or equal to 400, D2(x) in the relation (2) represents an intensity of the element (A) normalized with an intensity of silicon (Si) measured by the TOF-SIMS, x represents a depth from the end surface (in units of nm), and a2x+b2 represents a linear expression in terms of x obtained by approximating D2(x) using the least squares method for x which is greater than or equal to 200 and less than or equal to 400.

2. A glass substrate for Extreme Ultra-Violet Lithography (EUVL) comprising:
a first main surface having a rectangular shape;
a second main surface having a rectangular shape and being on an opposite side to the first main surface;
four end surfaces being orthogonal to the first main surface and the second main surface;
four first chamfered surfaces formed on boundaries between the first main surface and the four end surfaces respectively;
four secon

Assignees

• Agc Inc

Inventors

• Nara Takuma
• Tamura Masahiko
• Yamana Satoshi

Classifications

• G03F1/52

  Reflectors · CPC title

• C03C2201/42

  containing titanium · CPC title

• C03C2201/12

  containing fluorine (C03C2201/14 takes precedence) · CPC title

• G03F1/54

  Absorbers, e.g. of opaque materials · CPC title

• C03C2204/08

  Glass having a rough surface · CPC title