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US4600686A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of forming a resist mask resistant to plasma etching

Assignee: US Philips Corp
•
Filing: 1983-05-20
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Granted: 1986-07-15
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Expires: 2003-05-20
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Abstract

Abstract A mask which is resistant to a plasma etching treatment is formed by providing an etch resistant skin over a lithographically patterned radiation sensitive resist film present on a substrate. The etch resistant skin is formed by providing a layer of, for example, chromium on the patterned resist and on the exposed surface of the substrate, and then, baking so that the chromium reacts chemically with the resist to form the etch resistant skin around the patterned film. This method may be used for example to manufacture a photo mask using a chromium coated glass substrate, or during the manufacture of semiconductor devices on a semiconductor wafer substrate.

Inventors

  • 👤 Joseph Meyer
  • 👤 David J. Vinton

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 01:18
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/40; G03F7/405

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 140 words
A method of forming a plasma resistant mask on a substrate comprising the steps of forming a layer of radiation sensitive resist on a substrate, lithographically patterning said layer to form a patterned radiation sensitive resist layer, providing a layer of coating material of chromium on said patterned layer and said substrate, effecting a heat treatment of said coating layer such that said coating layer in contact with said resist layer chemically reacts to form a plasma etch resistant skin on said patterned resist layer, and removing unreacted portions of said coating layer to form said patterned resist layer with a skin coating of said coating layer as said mask on said substrate, wherein said patterned resist layer is formed on a surface layer of said substrate, said surface layer including the same material as said layer of coating material.
Claim 2
Independent Claim 140 words
A method of forming a plasma resistant mask on a substrate comprising the steps of forming a layer of radiation sensitive resist on a substrate, lithographically patterning said layer to form a patterned radiation sensitive resist layer, providing a layer of coating material of chromium on said patterned layer and said substrate, effecting a heat treatment of said coating layer such that said coating layer in contact with said resist layer chemically reacts to form a plasma etch resistant skin on said patterned resist layer, and removing unreacted portions of said coating layer to form said patterned resist layer with a skin coating of said coating layer as said mask on said substrate, wherein said patterned resist layer is formed on a surface layer of said substrate, said surface layer including the same material as said layer of coating material.
Claim 3
Dependent Claim 14 words
A method according to claim 1, wherein said radiation sensitive resist is positive acting.
Claim 4
Dependent Claim 18 words
A method according to claim 1, wherein said radiation sensitive resist is a cross-linked positive acting co-polymer resist.
Claim 5
Dependent Claim 22 words
A method according to claim 3, wherein said radiation sensitive resist includes a mixture of poly-(methyl methacrylate-co-methacrylic acid) and poly-(methyl methacrylate-co-methacryloyl chloride).
Claim 6
Dependent Claim 20 words
A method according to claim 1, wherein said radiation sensitive resist layer has a thickness of less than 0.25 micrometers.
Claim 7
Dependent Claim 11 words
A method according to claim 1, wherein said substrate is quartz.
Claim 8
Dependent Claim 13 words
A method according to claim 1, wherein said substrate is a semiconductor material.
Claim 9
Dependent Claim 11 words
A method according to claim 1, wherein said substrate is glass.
Claim 10
Dependent Claim 22 words
A method according to claim 1, wherein said heat treatment includes heating to a temperature of about 130° C. for 30 minutes.

References Cited (Backward Citations)

US4125650A Cited
US4259369A Cited
US4362598A Cited
US4389482A Cited
US4504574A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-07-14 1990-01-13 1990-07-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-07-14 1994-01-13 1994-07-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-07-14 1998-01-13 1998-07-15 $7700.00 Window Closed / Lapsed

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