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US5266424A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming pattern and method of manufacturing photomask using such method

Assignee: Renesas Electronics Corp
•
Filing: 1992-03-12
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Granted: 1993-11-30
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Expires: 2012-03-12
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Abstract

Abstract The present invention is mainly directed to provision of a method of producing a highly precise resist pattern, even when a high energy beam is used. Resist containing a base resin including a hydroxyl group, an acid generating agent irradiated with radiation for generating sulfonic acid, and a cross linking agent reacting with the hydroxyl group of the base resin by the catalytic action of the proton of the sulfonic acid thereby cross linking said base resin is applied onto a substrate. The resist is irradiated selectively with radiation, whereby the resist is divided into the exposed part and the non exposed part and the sulfonic acid is generated in the resist of the exposed part. The resist is heated to a first temperature so as to cross link the irradiated part of the resist. The resist is heated to a second temperature and exposed in an atmosphere of a silylating agent, and the surface of the exposed part of the resist is silylated. The resist is dry-developed with oxygen plasma.

Inventors

  • 👤 Takeshi Fujino
  • 👤 Yaichiro Watakabe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 21:42
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/36; G03F7/004; G03F7/039; G03F7/265

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 224 words
A method of forming a resist pattern, comprising the steps of: applying onto a substrate a resist containing a base resin including a hydroxyl group, an acid generating agent for generating a sulfonic acid when irradiated with radiation, and a cross linking agent for reacting with the hydroxyl group of the base resin by the catalytic action of the proton of the sulfonic acid to thereby cross link said base resin; selectively irradiating the resist with radiation, thereby dividing the resist into an exposed part and a non-exposed part and generating the sulfonic acid in the resist at the exposed part; heating the resist to a first temperature so as to cause the hydroxyl group of the base resin to react with the cross linking agent by the catalytic action of the proton of the sulfonic acid, thereby cross linking the exposed part of the resist; prior to dry developing the resist, selectively silylating the surface of the non-exposed part of the resist by heating the resist to a second temperature and exposing the resist in an atmosphere of a silylating agent; and dry-developing the resist with oxygen plasma to remove the exposed part of the resist and simultaneously convert a silylated layer formed on the surface of the non-exposed part of the resist to silicon dioxide, thereby forming a positive type resist pattern.
Claim 2
Independent Claim 224 words
A method of forming a resist pattern, comprising the steps of: applying onto a substrate a resist containing a base resin including a hydroxyl group, an acid generating agent for generating a sulfonic acid when irradiated with radiation, and a cross linking agent for reacting with the hydroxyl group of the base resin by the catalytic action of the proton of the sulfonic acid to thereby cross link said base resin; selectively irradiating the resist with radiation, thereby dividing the resist into an exposed part and a non-exposed part and generating the sulfonic acid in the resist at the exposed part; heating the resist to a first temperature so as to cause the hydroxyl group of the base resin to react with the cross linking agent by the catalytic action of the proton of the sulfonic acid, thereby cross linking the exposed part of the resist; prior to dry developing the resist, selectively silylating the surface of the non-exposed part of the resist by heating the resist to a second temperature and exposing the resist in an atmosphere of a silylating agent; and dry-developing the resist with oxygen plasma to remove the exposed part of the resist and simultaneously convert a silylated layer formed on the surface of the non-exposed part of the resist to silicon dioxide, thereby forming a positive type resist pattern.
Claim 3
Dependent Claim 16 words
A method as recited in claim 1, wherein said acid generating agent includes triphenyl sulfonium triflate.
Claim 4
Dependent Claim 16 words
A method as recited in claim 1, wherein said cross linking agent includes a melamine derivative.
Claim 5
Dependent Claim 13 words
A method as recited in claim 3, wherein said melamine derivative includes hexamethylol-melamine-hexamethylether.
Claim 6
Dependent Claim 23 words
A method as recited in claim 1, wherein the film thickness of said resist is in the range between 0.5 and 2 μm.
Claim 7
Dependent Claim 45 words
A method as recited in claim 1, wherein said cross linking agent is added in an amount of 5-30 weight % based on said base resin, and said acid generating agent is added in an amount of 3-15 weight % based on said base resin.
Claim 8
Dependent Claim 17 words
A method as recited in claim 1, wherein said second temperature is lower than said first temperature.
Claim 9
Dependent Claim 20 words
A method as recited in claim 1, wherein said first temperature is in the range between 50° and 150° C.
Claim 10
Dependent Claim 20 words
A method as recited in claim 1, wherein said second temperature is in the range between 40° and 140° C.
Claim 11
Dependent Claim 14 words
A method as recited in claim 1, wherein said base resin includes novolac resin.
Claim 12
Dependent Claim 24 words
A method as recited in claim 1, wherein said radiation includes an electron beam of energy in the range between 1 and 100 keV.
Claim 13
Dependent Claim 16 words
A method as recited in claim 1, wherein said silylating agent includes 1, 1, 3, 3-tetramethyldisilazane.
Claim 14
Independent Claim 255 words
A method of manufacturing a photomask, comprising the steps of: forming a metal layer on a glass substrate; applying onto the metal layer a resist containing a base resin including a hydroxyl group, an acid generating agent for generating a sulfonic acid when irradiated with radiation, and a cross linking agent for reacting with the hydroxyl group of the base resin by the catalytic action of the proton of the sulfonic acid to thereby cross link the base resin; selectively irradiating the resist with radiation, thereby dividing the resist into an exposed part and a non-exposed part and generating the sulfonic acid in the resist at the exposed part; heating the resist to a first temperature so as to cross link the exposed part of the resist by causing the reaction of the hydroxyl group of the base resin and the cross linking agent in the presence of the proton of the sulfonic acid as the catalyst; prior to dry developing the resist, selectively silylating the surface of the non-exposed part of the resist by heating the resist to a second temperature and exposing the resist in an atmosphere of a silylating agent; dry-developing said resist with oxygen plasma to remove the exposed part of the resist and simultaneously convert a silylated layer formed on the surface of the non-exposed part of the resist to silicon dioxide, thereby forming a positive type resist pattern; selectively etching the metal layer using the positive type resist pattern as a mask; and removing the positive type resist pattern.
Claim 15
Independent Claim 255 words
A method of manufacturing a photomask, comprising the steps of: forming a metal layer on a glass substrate; applying onto the metal layer a resist containing a base resin including a hydroxyl group, an acid generating agent for generating a sulfonic acid when irradiated with radiation, and a cross linking agent for reacting with the hydroxyl group of the base resin by the catalytic action of the proton of the sulfonic acid to thereby cross link the base resin; selectively irradiating the resist with radiation, thereby dividing the resist into an exposed part and a non-exposed part and generating the sulfonic acid in the resist at the exposed part; heating the resist to a first temperature so as to cross link the exposed part of the resist by causing the reaction of the hydroxyl group of the base resin and the cross linking agent in the presence of the proton of the sulfonic acid as the catalyst; prior to dry developing the resist, selectively silylating the surface of the non-exposed part of the resist by heating the resist to a second temperature and exposing the resist in an atmosphere of a silylating agent; dry-developing said resist with oxygen plasma to remove the exposed part of the resist and simultaneously convert a silylated layer formed on the surface of the non-exposed part of the resist to silicon dioxide, thereby forming a positive type resist pattern; selectively etching the metal layer using the positive type resist pattern as a mask; and removing the positive type resist pattern.
Claim 16
Dependent Claim 14 words
A method as recited in claim 13, wherein said radiation includes an electron beam.
Claim 17
Dependent Claim 16 words
A method as recited in claim 13, wherein said acid generating agent includes triphenyl sulfonium triflate.
Claim 18
Dependent Claim 16 words
A method as recited in claim 13, wherein said cross linking agent includes a melamine derivative.
Claim 19
Dependent Claim 13 words
A method as recited in claim 16, wherein said melamine derivative includes hexamethylol-melamine-hexamethylether.
Claim 20
Dependent Claim 20 words
A method as recited in claim 13, wherein said first temperature is in the range between 50° and 150° C.
Claim 21
Dependent Claim 20 words
A method as recited in claim 13, wherein said second temperature is in the range between 40° and 140° C.

References Cited (Backward Citations)

US4837124A Cited
US4863827A Cited
US4978594A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-11-29 1997-05-31 1997-11-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-11-29 2001-05-31 2001-11-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-11-29 2005-05-31 2005-11-30 $7700.00 Window Closed / Lapsed

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