US4873162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray mask and a manufacture method therefor
Assignee: Mitsubishi Electric Corp
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Filing: 1987-08-14
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Granted: 1989-10-10
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Expires: 2007-08-14
Abstract
Abstract An x-ray mask for x-ray lithography has an x-ray absorber pattern which is formed from a Ti-W alloy with a Ti content of 0.5-10 weight %. A method for the manufacture of the x-ray mask comprises sequentially forming a first film, a Ti-W alloy film with a Ti content of approximately 0.5-10 weight %, and a third film on a mask substrate and coating the third film with an electron beam-sensitive resist, exposing the resist to an electron beam and then developing the exposed resist to form a resist pattern, using the resist pattern as a mask and selectively etching the third film to form a pattern, and using the pattern as a mask and selectively etching the Ti-W alloy film with a reactive gas to form an absorber pattern. The Ti-W alloy film is preferably formed by sputtering in an atmosphere of argon and nitrogen gas with a nitrogen content of approximately 30-50%, whereby nitrogen is included in the Ti-W alloy film.
Inventors
- 👤 Nobuyuki Yoshioka
- 👤 Nobuo Fujiwara
- 👤 Yaichirou Watakabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:14
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/22
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
49 words
An x-ray mask comprising: a mask substrate that is permeable to x-rays; and an x-ray absorber disposed on said substrate and formed into a pattern, said absorber being made from a Ti-W alloy with a Ti content of approximately 0.5-10 weight % in a sufficient thickness to absorb x-rays.
Claim 2
Dependent Claim
49 words
An x-ray mask comprising: a mask substrate that is permeable to x-rays; and an x-ray absorber disposed on said substrate and formed into a pattern, said absorber being made from a Ti-W alloy with a Ti content of approximately 0.5-10 weight % in a sufficient thickness to absorb x-rays.
Claim 3
Dependent Claim
48 words
An x-ray mask comprising: a mask substrate that is permeable to x-rays; and an x-ray absorber disposed on said substrate, formed into a pattern, made from a Ti-W alloy containing nitrogen and having a Ti content of approximately 0.5-10 weight %, and of sufficient thickness to absorb x-rays.
Claim 4
Dependent Claim
48 words
An x-ray mask comprising: a mask substrate that is permeable to x-rays; and an x-ray absorber disposed on said substrate, formed into a pattern, made from a Ti-W alloy containing nitrogen and having a Ti content of approximately 0.5-10 weight %, and of sufficient thickness to absorb x-rays.
Claim 5
Dependent Claim
161 words
A manufacturing method for an x-ray mask comprising: forming a first film which serves as an etching stopper on a mask substrate which is permeable to x-rays, forming a Ti-W alloy film having a Ti content of approximately 0.5-10 weight % on said first film in a thickness sufficient to absorb x-rays, forming a third film on said alloy film, and depositing an electron beam-sensitive resist on said third film; exposing said resist in a prescribed pattern to an electron beam and then developing said exposed resist to form a resist pattern; selectively etching said third film while using said resist pattern as a mask to form a pattern in said third film; and selectively etching said Ti-W alloy film with a reactive gas by reactive ion etching while using said pattern of the third film as a mask and the first film as an etchant stop for the reactive gas to form said Ti-W alloy film into a prescribed pattern.
Claim 6
Dependent Claim
161 words
A manufacturing method for an x-ray mask comprising: forming a first film which serves as an etching stopper on a mask substrate which is permeable to x-rays, forming a Ti-W alloy film having a Ti content of approximately 0.5-10 weight % on said first film in a thickness sufficient to absorb x-rays, forming a third film on said alloy film, and depositing an electron beam-sensitive resist on said third film; exposing said resist in a prescribed pattern to an electron beam and then developing said exposed resist to form a resist pattern; selectively etching said third film while using said resist pattern as a mask to form a pattern in said third film; and selectively etching said Ti-W alloy film with a reactive gas by reactive ion etching while using said pattern of the third film as a mask and the first film as an etchant stop for the reactive gas to form said Ti-W alloy film into a prescribed pattern.
Claim 7
Dependent Claim
33 words
A method as claimed in claim 3, wherein said first and third films are made of a material which is more difficult to etch with said reactive gas than said Ti-W alloy film.
Claim 8
Dependent Claim
20 words
A method as claimed in claim 4, wherein said first and third lower films are made of SiO 2 .
Claim 9
Dependent Claim
27 words
A method as claimed in claim 3, wherein said reactive gas for etching said Ti-W alloy film is a mixture of CF 4 and O 2 .
Claim 10
Dependent Claim
37 words
A method as claimed in claim 3, wherein said Ti-W alloy film is formed on said first film by sputtering in an atmosphere comprising argon and nitrogen gas, whereby nitrogen is included in said Ti-W alloy film.
Claim 11
Dependent Claim
17 words
A method as claimed in claim 7, wherein the nitrogen content of said atmosphere is approximately 30-50%.
Claim 12
Dependent Claim
159 words
A manufacturing method for an x-ray mask comprising: forming a first film which serves as an etching stopper on a mask substrate which is permeable to x-rays, forming a Ti-W alloy film containing nitrogen and having a Ti content of approximately 0.5-10 weight % on said first film in a thickness sufficient to absorb x-rays, forming a third film, depositing an electron beam-sensitive resist on said third film; exposing said resist in a prescribed pattern to an electron beam and then developing said exposed resist to form a resist pattern; selectively etching said third film while using said resist pattern as a mask to form a pattern in said third film; and selectively etching said Ti-W aloy film with a reactive gas by reactive ion etching while using said pattern of the third film as a mask and the first film as an etchant stop for the reactive gas to form said Ti-W alloy film into a prescribed pattern.
Claim 13
Dependent Claim
159 words
A manufacturing method for an x-ray mask comprising: forming a first film which serves as an etching stopper on a mask substrate which is permeable to x-rays, forming a Ti-W alloy film containing nitrogen and having a Ti content of approximately 0.5-10 weight % on said first film in a thickness sufficient to absorb x-rays, forming a third film, depositing an electron beam-sensitive resist on said third film; exposing said resist in a prescribed pattern to an electron beam and then developing said exposed resist to form a resist pattern; selectively etching said third film while using said resist pattern as a mask to form a pattern in said third film; and selectively etching said Ti-W aloy film with a reactive gas by reactive ion etching while using said pattern of the third film as a mask and the first film as an etchant stop for the reactive gas to form said Ti-W alloy film into a prescribed pattern.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-09 | 1993-04-10 | 1993-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-09 | 1997-04-10 | 1997-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-09 | 2001-04-10 | 2001-10-10 | $7700.00 | Window Closed / Lapsed |