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US4942108A Expired / Lapsed US ⏱️ 0.0 years remaining

Process of making diazoquinone sensitized polyamic acid based photoresist compositions having reduced dissolution rates in alkaline developers

Assignee: International Business Machines Corp
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Filing: 1989-09-08
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Granted: 1990-07-17
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Expires: 2009-09-08
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Abstract

Abstract The dissolution rate in alkaline developer solutions of image-wise exposed photoresist systems based on diazoquinone sensitized polyamic acid is reduced to prepare relief images of fine line resolution by reducing the acidity of the polyamic acid prior to exposure.

Inventors

  • 👤 Wayne M. Moreau
  • 👤 Kaolin N. Chiong
  • 👤 Ming-Fea Chow
  • 👤 Nancy W. Snyder

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 17:15
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/023; G03F7/0233

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 222 words
A process for forming a resist mask comprising the steps of (1) coating onto a substrate a layer comprising a mixture of polyamic acid material of reduced acidity comprising a polyamic acid having the general formula ##STR7## wherein Q is C or C=O, R is a divalent aromatic or aliphatic radical having no active hydrogen, R 1 is hydrogen or an alkyl group containing 1 to 3 carbon atoms, and R 2 and R 3 are independently selected from H, CH 3 , C n H 2n+1 where n is a positive integer, and CF 3 , m is an integer from 0 to 1 and p is a positive integer, which is reacted or blended to form (a) a polyamic acid material having a level of acidity which is reduced by from about 10 to about 40 percent of the original polyamic acid and (b) a diazoquinone photosensitizer, each of (a) and (b) being present in sufficient quantity to form a photoresist composition which, after radiation exposure and development in alkaline solution, produces a resist image of fine line resolution, (2) image-wise exposing said layer to a source of radiation and then (3) developing said layer in an alkaline developer solution to remove the exposed portion of the layer whereby the exposed photoresist exhibits a reduced dissolution rate in the developer.
Claim 2
Dependent Claim 222 words
A process for forming a resist mask comprising the steps of (1) coating onto a substrate a layer comprising a mixture of polyamic acid material of reduced acidity comprising a polyamic acid having the general formula ##STR7## wherein Q is C or C=O, R is a divalent aromatic or aliphatic radical having no active hydrogen, R 1 is hydrogen or an alkyl group containing 1 to 3 carbon atoms, and R 2 and R 3 are independently selected from H, CH 3 , C n H 2n+1 where n is a positive integer, and CF 3 , m is an integer from 0 to 1 and p is a positive integer, which is reacted or blended to form (a) a polyamic acid material having a level of acidity which is reduced by from about 10 to about 40 percent of the original polyamic acid and (b) a diazoquinone photosensitizer, each of (a) and (b) being present in sufficient quantity to form a photoresist composition which, after radiation exposure and development in alkaline solution, produces a resist image of fine line resolution, (2) image-wise exposing said layer to a source of radiation and then (3) developing said layer in an alkaline developer solution to remove the exposed portion of the layer whereby the exposed photoresist exhibits a reduced dissolution rate in the developer.
Claim 3
Dependent Claim 24 words
The process of claim 1 wherein the polyamic acid of reduced acidity is prepared by partially imidizing the polyamic acid prior to radiation exposure.
Claim 4
Dependent Claim 24 words
The process of claim 2 wherein the polyamic acid is partially imidized to an imidization level of from about 10 to about 30 percent.
Claim 5
Dependent Claim 12 words
The process of claim 1 wherein the diazoquinone photosensitizer is 2,3,4-tri[(6-diazo-5,6-dihydro-5-oxo-napthalenyl) sulfonyl-oxy]benzophenone.
Claim 6
Dependent Claim 20 words
The process of claim 1 wherein the diazoquinone photosensitizer is 4,8-bis[6-diazo-5,6-dihydro-5-oxo-1-naphthalenyl) sulfonyl oxy methyl] tricyclo [5.2.1.0 2 ,6 ] decane.
Claim 7
Dependent Claim 27 words
The process of claim 1 wherein the diazoquinone sensitizer is incorporated in the photoresist composition at a concentration of about 5 to about 25 percent by weight.
Claim 8
Dependent Claim 13 words
The process of claim 1 wherein the polyamic acid has the formula ##STR8##
Claim 9
Dependent Claim 46 words
The process of claim 1 wherein the layer is image-wise exposed with ultraviolet light in step (2), and after exposure is baked at about 100° to about 130° C. and blanket exposed with ultraviolet light whereby upon development in step (3) a negative resist is produced.
Claim 10
Independent Claim 186 words
A method of reducing the dissolution rate of a photoresist composition comprised of a mixture of a polyamic acid and a diazoquinone photosensitizer, which comprises reducing the acidity of a polyamic acid having the general formula ##STR9## wherein Q is C or C=O, R is a divalent aromatic or aliphatic radical having no active hydrogen, R 1 is hydrogen or an alkyl group containing 1 to 3 carbon atoms, and R 2 and R 3 are independently selected from H, CH 3 , C n H 2n+1 where n is a positive integer, and CF 3 , m is an integer from 0 to 1 and p is a positive integer, by reacting or blending said polyamic acid to form (a) a polyamic acid material having a level of acidity which is reduced by from about 10 to about 40 percent of the original polyamic acid and mixing (a) with (b) a diazoquinone photosensitizer, each of (a) and (b) being present in sufficient quantity to form a photoresist composition which, after radiation exposure and development in alkaline solution, produces a resist image of fine line resolution.
Claim 11
Independent Claim 186 words
A method of reducing the dissolution rate of a photoresist composition comprised of a mixture of a polyamic acid and a diazoquinone photosensitizer, which comprises reducing the acidity of a polyamic acid having the general formula ##STR9## wherein Q is C or C=O, R is a divalent aromatic or aliphatic radical having no active hydrogen, R 1 is hydrogen or an alkyl group containing 1 to 3 carbon atoms, and R 2 and R 3 are independently selected from H, CH 3 , C n H 2n+1 where n is a positive integer, and CF 3 , m is an integer from 0 to 1 and p is a positive integer, by reacting or blending said polyamic acid to form (a) a polyamic acid material having a level of acidity which is reduced by from about 10 to about 40 percent of the original polyamic acid and mixing (a) with (b) a diazoquinone photosensitizer, each of (a) and (b) being present in sufficient quantity to form a photoresist composition which, after radiation exposure and development in alkaline solution, produces a resist image of fine line resolution.
Claim 12
Dependent Claim 18 words
The method of claim 9 wherein the polyamic acid or reduced acidity is a partially imidized polyamic acid.
Claim 13
Dependent Claim 24 words
The method of claim 10 wherein the polyamic acid is partially imidized to an imidization level of from about 20 to about 40 percent.
Claim 14
Dependent Claim 30 words
The method of claim 9 wherein the polyamic acid of reduced acidity is a carboxylate amine salt formed by the reaction of a polyamic acid and a basic organic compound.
Claim 15
Dependent Claim 38 words
The method of claim 9 wherein the polyamic acid of reduced acidity is a polyamic acid wherein a portion of the free carboxylic acid groups of the polyamic acid have been neutralized by reaction with an organic base.
Claim 16
Dependent Claim 11 words
The method of claim 13 wherein the organic base is triethylamine.
Claim 17
Dependent Claim 47 words
The method of claim 9 wherein the polyamic acid of reduced acidity is selected from the group consisting of a blend of a polyamic acid with (a) an ester derivative thereof, (b) a copolymer of the polyamic acid and an ester derivative thereof and (c) mixtures thereof.
Claim 18
Dependent Claim 13 words
The method of claim 9 wherein the polyamic acid has the formula ##STR10##

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Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-07-16 1994-01-15 1994-07-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-07-16 1998-01-15 1998-07-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-07-16 2002-01-15 2002-07-17 $7700.00 Window Closed / Lapsed

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