EP0073303A1
Expired / Lapsed
EP
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Process for forming a patterned mask using a positive electron beam resist
Assignee: International Business Machines Corp
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Filing: 1982-06-08
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Granted: —
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Expires: 2002-06-08
Abstract
Abstract A positive working electron beam resist comprising a resinous condensation product of formaldehyde with a phenol or a cresol having a chloro substituent ortho to the hydroxyl group on its aromatic ring is imagewise exposed to electron beam irradiation and then the exposed portion of the resist is dissolved away to leave a petterned mask.
Inventors
- 👤 James Economy
- 👤 Roy John Gritter
- 👤 Hiroyuki Hiraoka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 07:01
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
65 words
A process for forming a patterned mask by the steps of imagewise exposing a positive-acting resist to electron beam irradiation, and selectively removing the exposed portion of the resist by treating it with a solvent, characterised in that the resist comprises a condensation product of formaldehyde with a phenol or a cresol having a chloro substituent ortho to the hydroxyl group on its aromatic ring.
Claim 2
Dependent Claim
65 words
A process for forming a patterned mask by the steps of imagewise exposing a positive-acting resist to electron beam irradiation, and selectively removing the exposed portion of the resist by treating it with a solvent, characterised in that the resist comprises a condensation product of formaldehyde with a phenol or a cresol having a chloro substituent ortho to the hydroxyl group on its aromatic ring.
Claim 3
Dependent Claim
33 words
A process as claimed in claim 1, wherein the resist is formed by the condensation of formaldehyde with an ortho-chloro-substituted phenol or cresol in a reaction catalyzed by the presence of oxalic acid.
Claim 4
Dependent Claim
21 words
A process as claimed in claim 1 or claim 2, wherein the resist is a condensation product of formaldehyde with ortho-chloro-phenol.
References Cited (Backward Citations)
US4123279A
Cited
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