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US4920028A Expired / Lapsed US ⏱️ 0.0 years remaining

High contrast high thermal stability positive photoresists with mixed cresol and hydroxybenzaldehyde prepared novolak and photosensitive diazoquinone

Assignee: EMD Performance Materials Corp
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Filing: 1988-08-02
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Granted: 1990-04-24
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Expires: 2008-08-02
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Abstract

Abstract Novolak resins are provided which are the condensation product of (a) a phenol, phenol derivative, or mixtures thereof, and (b) a mixture of formaldehyde or a formaldehyde precursor and an aromatic aldehyde. When the aromatic aldehyde is a monohydroxy aromatic aldehyde, the novolak resin is especially useful in positive photoresist formulations.

Inventors

  • 👤 Richard M. Lazarus
  • 👤 Randall Kautz
  • 👤 Sunit S. Dixit

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 04:16
CPC Classifications
C; C08; C08G; C08G8/00; C08G8/04; G; G03; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/023; G03F7/0233; G03F7/0236

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 99 words
In a positive photoresist comprising an admixture of a bindingly effective amount of a novolak resin and a photoimaging amount of diazoquinone photosensitizer the improvement comprising employing as the novolak resin the condensation product of (a) a mixture of m- and p-cresol and (b) a mixture of aldehydes comprising formaldehyde or a formaldehyde precursor and a monohydroxy aromatic aldehyde selected from the group consisting of 2-hydroxybenzaldehyde, 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, wherein the cresol and aldehyde components of the novolak resin are present in the following amounts: ##EQU3## and wherein the m- and p-cresol are present in the following amounts: ##EQU4##
Claim 2
Dependent Claim 99 words
In a positive photoresist comprising an admixture of a bindingly effective amount of a novolak resin and a photoimaging amount of diazoquinone photosensitizer the improvement comprising employing as the novolak resin the condensation product of (a) a mixture of m- and p-cresol and (b) a mixture of aldehydes comprising formaldehyde or a formaldehyde precursor and a monohydroxy aromatic aldehyde selected from the group consisting of 2-hydroxybenzaldehyde, 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, wherein the cresol and aldehyde components of the novolak resin are present in the following amounts: ##EQU3## and wherein the m- and p-cresol are present in the following amounts: ##EQU4##
Claim 3
Dependent Claim 93 words
A positive photoresist composition comprising an admixture of: A. a bindingly effective amount of a novolak resin comprising the condensation product of (a) a mixture of m- and p-cresol and (b) a mixture of aldehydes comprising formaldehyde or a formaldehyde precursor and a monohydroxy aromatic aldehyde selected from the group consisting of 2-hydroxybenzaldehyde 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, wherein the cresol and aldehyde components of the novolak resin are present in the following amounts: ##EQU5## and wherein the m- and p-cresol are present in the following amounts: ##EQU6## B. a photoimaging amount of diazoquinone photosensitizer.
Claim 4
Dependent Claim 93 words
A positive photoresist composition comprising an admixture of: A. a bindingly effective amount of a novolak resin comprising the condensation product of (a) a mixture of m- and p-cresol and (b) a mixture of aldehydes comprising formaldehyde or a formaldehyde precursor and a monohydroxy aromatic aldehyde selected from the group consisting of 2-hydroxybenzaldehyde 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde, wherein the cresol and aldehyde components of the novolak resin are present in the following amounts: ##EQU5## and wherein the m- and p-cresol are present in the following amounts: ##EQU6## B. a photoimaging amount of diazoquinone photosensitizer.
Claim 5
Dependent Claim 20 words
The positive photoresist of claim 2 wherein the photosensitizer is a naphthoquinone diazide sensitizer or mixture of naphthoquinone diazide sensitizers.
Claim 6
Dependent Claim 29 words
The positive photoresist of claim 3 wherein the naphthoquinone diazide sensitizer is selected from the group consisting of esters of 1,2-naphthoquinone-2-diazo-4-sulfonic acid, esters of 1,2-naphthoquinone-2-diazo-5-sulfonic acid, and mixtures thereof.
Claim 7
Dependent Claim 30 words
The positive photoresist of claim 4 wherein the naphthoquinone diazide sensitizer is selected from the group consisting of 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-4-sulfonic acid monoester; 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-4-sulfonic acid diester; 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-4-sulfonic acid triester and mixtures thereof.
Claim 8
Dependent Claim 30 words
The positive photoresist of claim 4 wherein the naphthoquinone diazide sensitizer is selected from the group consisting of 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-5-sulfonic acid monoester; 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-5-sulfonic acid diester; 2,3,4-trihydroxybenzophenone-1,2-naphthoquinone-2-diazo-5-sulfonic acid triester and mixtures thereof.

References Cited (Backward Citations)

US4308368A Cited
US4477553A Cited
US4536465A Cited
US4642282A Cited
EP0211667A2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-23 1993-10-23 1994-04-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-23 1997-10-23 1998-04-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-23 2001-10-23 2002-04-24 $7700.00 Window Closed / Lapsed

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