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EP0244572A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Capped two-layer resist process

Assignee: International Business Machines Corp
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Filing: 1987-02-17
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Granted: —
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Expires: 2007-02-17
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Abstract

Abstract A method of producing a resist image comprising: (a) providing a substrate with a layer of a wet developable resist material as a bottom resist layer and with a layer of a wet developable resist material as a top resist layer, wherein (i) the sensitivity to radiation of the resist material of the top resist layer differs significantly from the sensitivity to radiation of the resist material of the bottom resist layer, and (ii) the resist material of the top resist layer contains sites capable of reacting with a silylating agent; (b) imagewise exposing to radiation the top resist layer, the imagewise exposing of the top resist layer being such that the bottom resist layer is substantially unaffected by said imagewise exposing; (c) wet developing the top resist layer to produce a top layer image; (d) reacting the developed top resist layer with a silylating agent to produce an etch resistant pattern of the top resist layer on the bottom resist layer and also to render the top resist layer resistant to the development to be used for subsequent development of the bottom resist layer; (e) exposing the bottom resist layer through the top layer resist image to radiation capable of rendering the resist material of the bottom resist layer in the exposed areas developable; and (f) developing the exposed bottom resist layer to uncover the substrate in the imagewise exposed and developed areas.

Inventors

  • 👤 Christopher Francis Lyons

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-01 17:13
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/09; G03F7/095; G03F7/26; G03F7/40; G03F7/405

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 234 words
A method of producing a resist image comprising: (a) providing a substrate with a layer of a wet developable resist material as a bottom resist layer and with a layer of a wet developable resist material as a top resist layer, wherein (i) the sensitivity to radiation of the resist material of the top resist layer differs significantly from the sensitivity to radiation of the resist material of the bottom resist layer, and (ii) the resist material of the top resist layer contains sites capable of reacting with a silylating agent; (b) imagewise exposing to radiation the top resist layer, the imagewise exposing of the top resist layer being such that the bottom resist layer is substantially unaffected by said imagewise exposing; (c) wet developing the top resist layer to produce a top layer image; (d) reacting the developed top resist layer with a silylating agent to produce an etch resistant pattern of the top resist layer on the bottom resist layer and also to render the top resist layer resistant to the development to be used for subsequent development of the bottom resist layer; (e) exposing the bottom resist layer through the top layer resist image to radiation capable of rendering the resist material of the bottom resist layer in the exposed areas developable; and (f) developing the exposed bottom resist layer to uncover the substrate in the imagewise exposed and developed areas.
Claim 2
Independent Claim 234 words
A method of producing a resist image comprising: (a) providing a substrate with a layer of a wet developable resist material as a bottom resist layer and with a layer of a wet developable resist material as a top resist layer, wherein (i) the sensitivity to radiation of the resist material of the top resist layer differs significantly from the sensitivity to radiation of the resist material of the bottom resist layer, and (ii) the resist material of the top resist layer contains sites capable of reacting with a silylating agent; (b) imagewise exposing to radiation the top resist layer, the imagewise exposing of the top resist layer being such that the bottom resist layer is substantially unaffected by said imagewise exposing; (c) wet developing the top resist layer to produce a top layer image; (d) reacting the developed top resist layer with a silylating agent to produce an etch resistant pattern of the top resist layer on the bottom resist layer and also to render the top resist layer resistant to the development to be used for subsequent development of the bottom resist layer; (e) exposing the bottom resist layer through the top layer resist image to radiation capable of rendering the resist material of the bottom resist layer in the exposed areas developable; and (f) developing the exposed bottom resist layer to uncover the substrate in the imagewise exposed and developed areas.
Claim 3
Dependent Claim 19 words
The method of Claim 1, wherein the top resist layer is a layer of a positive working resist material.
Claim 4
Dependent Claim 19 words
The method of Claim 1, wherein the top resist layer is a layer of a negative working resist material.
Claim 5
Dependent Claim 26 words
The method of Claim 2, wherein the resist material of the bottom resist layer is a positive working resist material and is sensitive to U.V. radiation.
Claim 6
Dependent Claim 16 words
The method of Claim 2, wherein the positive working resist material is a novolac/diazoquinone resist material.
Claim 7
Dependent Claim 20 words
The method of Claim 5, wherein the resist material of the bottom resist layer is sensitive to deep U.V. radiation.
Claim 8
Dependent Claim 25 words
The method of Claim 6, wherein the resist material sensitive to deep U.V. radiation is selected from the group consisting of polymethyl-metharcylate and derivatives thereof.
Claim 9
Dependent Claim 24 words
The method of Claim 1, wherein the resist material of the bottom resist layer is an aqueous-base-developable or organic solvent solution developable resist material.
Claim 10
Dependent Claim 37 words
The method of Claim 1, wherein the resist material of the bottom resist layer is (i) a copolymer of methylmethacrylate with methacrylic acid or methacrylic anhydride or (ii) a terpolymer of methylmethacrylate, methacrylic acid and methacrylic anhydride.
Claim 11
Dependent Claim 13 words
The method of Claim 1, wherein the silylating agent is a multifunctional silizane.
Claim 12
Dependent Claim 11 words
The method of Claim 10, wherein the silylating agent is hexamethylcyclotrisilizane.
Claim 13
Dependent Claim 23 words
The method of Claim 6, wherein in step (f) the method comprises developing the exposed bottom resist layer by a dry etch development.

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