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US5409801A Expired / Lapsed US ⏱️ 0.0 years remaining

Electron beam lithography

Assignee: EIDP Inc
•
Filing: 1994-04-15
•
Granted: 1995-04-25
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Expires: 2014-04-15
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Abstract

Abstract A method for improving the resolution of an electron resist pattern on a substrate coated with a polymeric electron resist film is disclosed which provides an external coating layer of dried polymer selected from the group consisting of water-soluble polymers and poly(m-phenylene isophthalamide), or of a mixture consisting essentially of said dried polymer and hexavalent tungsten compounds wherein the weight ratio of the tungsten compounds to polymer is up to about 1:1. Also disclosed are substrates coated with a polymeric resist film wherein the resist film consists essentially of such external layers, or wherein an external coating layer of said polymer-tungsten compound mixture is provided.

Inventors

  • 👤 Robert V. Kasowski
  • 👤 Sau L. Tang

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 00:44
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/094; G03F7/038; G03F7/20; G03F7/2051; G03F7/2059; Y; Y10; Y10S; Y10S430/00; Y10S430/1053; Y10S430/1055; Y10S430/106; Y10S430/11; Y10S430/112; Y10S430/143

Claims Analysis

Total Claims: 26
Claim 1
Independent Claim 93 words
A substrate coated with a dried polymeric electron beam resist film, characterized by: said electron beam resist film consisting essentially of an external layer of either external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and said external layer being the only polymeric layer of the coated substrate.
Claim 2
Dependent Claim 93 words
A substrate coated with a dried polymeric electron beam resist film, characterized by: said electron beam resist film consisting essentially of an external layer of either external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and said external layer being the only polymeric layer of the coated substrate.
Claim 3
Dependent Claim 64 words
A substrate coated with a dried polymeric electron beam resist film characterized by having an external coating layer of a mixture consisting essentially of (i) external coating polymer selected from the group consisting of water-soluble polymers and poly(m-phenylene isophthalamide) and (ii) at least one hexavalent tungsten compound; wherein the weight ratio of component (ii) to component (i) is from about 0.01:1 to about 1:1.
Claim 4
Dependent Claim 64 words
A substrate coated with a dried polymeric electron beam resist film characterized by having an external coating layer of a mixture consisting essentially of (i) external coating polymer selected from the group consisting of water-soluble polymers and poly(m-phenylene isophthalamide) and (ii) at least one hexavalent tungsten compound; wherein the weight ratio of component (ii) to component (i) is from about 0.01:1 to about 1:1.
Claim 5
Dependent Claim 29 words
The coated substrate of claim 2 wherein the external coating polymer is selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly-(m-phenylene isophthalamide).
Claim 6
Dependent Claim 128 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern characterized by: in step (a), providing an external layer by coating with a solution containing a mixture of (i) external coating polymer selected from the group consisting of water-soluble polymers and poly(m-phenylene isophthalamide), and (ii) one or more hexavalent tungsten compounds, wherein the weight ratio of component (ii) to component (i) is from about 0.1:1 to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said mixture of polymer component and tungsten component.
Claim 7
Dependent Claim 128 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern characterized by: in step (a), providing an external layer by coating with a solution containing a mixture of (i) external coating polymer selected from the group consisting of water-soluble polymers and poly(m-phenylene isophthalamide), and (ii) one or more hexavalent tungsten compounds, wherein the weight ratio of component (ii) to component (i) is from about 0.1:1 to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said mixture of polymer component and tungsten component.
Claim 8
Dependent Claim 38 words
The method of claim 4 wherein said external layer is applied to the substrate as the only polymer-containing layer of said coated substrate and is an electron beam resist film from about 20 to about 600 nm thick.
Claim 9
Dependent Claim 31 words
The method of claim 4 wherein said external layer is applied to an electron beam resist consisting essentially of dried polymer and is from about 20 to about 600 nm thick.
Claim 10
Dependent Claim 20 words
The method of claim 6 wherein the external layer is applied to an electron beam resist consisting essentially of polymethylmethacrylate.
Claim 11
Dependent Claim 29 words
The method of claim 4 wherein the external coating polymer is selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly (m-phenylene isophthalamide).
Claim 12
Dependent Claim 26 words
The method of claim 8 wherein the external coating polymer is polyvinyl pyrrolidone or poly(m-phenylene isophthalamide); and wherein component (ii) consists essentially of WCl 6 .
Claim 13
Dependent Claim 166 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern, characterized by: in step (a), applying to said substrate an external polymer-containing electron beam resist, by coating the substrate with a solution containing either external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said external coating polymer or of said mixture of polymer component and tungsten component; said external layer being the only polymeric layer of the coated substrate.
Claim 14
Dependent Claim 166 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern, characterized by: in step (a), applying to said substrate an external polymer-containing electron beam resist, by coating the substrate with a solution containing either external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said external coating polymer or of said mixture of polymer component and tungsten component; said external layer being the only polymeric layer of the coated substrate.
Claim 15
Dependent Claim 20 words
The method of claim 10 wherein said external electron beam resist is from about 20 to about 600 nm thick.
Claim 16
Dependent Claim 18 words
The method of claim 10 wherein the external electron beam resist consists essentially of said external coating polymer.
Claim 17
Dependent Claim 26 words
The method of claim 12 wherein the external coating polymer is selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone and hydroxypropyl cellulose.
Claim 18
Dependent Claim 13 words
The method of claim 12 wherein the external coating polymer is polyvinyl alcohol.
Claim 19
Dependent Claim 25 words
The method of claim 10 wherein the external electron beam resist consists essentially of a mixture of said external coating polymer and hexavalent tungsten compounds.
Claim 20
Dependent Claim 25 words
The method of claim 15 wherein the external coating polymer is polyvinyl pyrrolidone or poly(m-phenylene isophthalamide); and wherein the tungsten compound is WCl 6 .
Claim 21
Dependent Claim 171 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern, characterized by: in step (a), an external polymer-containing electron beam resist is applied to an electron beam resist consisting essentially of dried polymer on said substrate by coating the electron beam resist consisting essentially of dried polymer with a solution containing external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said external coating polymer or of said mixture of polymer component and tungsten component.
Claim 22
Dependent Claim 171 words
An electron beam lithography process comprising the steps of (a) coating a substrate with a polymeric electron beam resist film, (b) forming an electron beam resist pattern by exposing the electron beam resist film to an electron beam, and (c) developing the electron beam resist pattern, characterized by: in step (a), an external polymer-containing electron beam resist is applied to an electron beam resist consisting essentially of dried polymer on said substrate by coating the electron beam resist consisting essentially of dried polymer with a solution containing external coating polymer selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone, hydroxypropyl cellulose and poly(m-phenylene isophthalamide), or a mixture consisting essentially of (i) said external coating polymer and (ii) at least one hexavalent tungsten compound wherein the weight ratio of component (ii) to component (i) is up to about 1:1; and drying the coated solution to provide a coated substrate having a dried external layer of said external coating polymer or of said mixture of polymer component and tungsten component.
Claim 23
Dependent Claim 20 words
The method of claim 17 wherein said external electron beam resist is from about 20 to about 600 nm thick.
Claim 24
Dependent Claim 22 words
The method of claim 18 wherein the external electron beam resist is applied to an electron beam resist consisting essentially of polymethylmethacrylate.
Claim 25
Dependent Claim 18 words
The method of claim 17 wherein the external electron beam resist consists essentially of said external coating polymer.
Claim 26
Dependent Claim 26 words
The method of claim 20 wherein the external coating polymer is selected from the group consisting of polyvinyl alcohol, polyvinyl acetate, polyvinyl pyrrolidone and hydroxypropyl cellulose.

References Cited (Backward Citations)

US5139922A Cited

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Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-04-24 1998-10-24 1999-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-04-24 2002-10-24 2003-04-25 $3760.00 Window Closed / Lapsed
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