US4377631A
Expired / Lapsed
US
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Positive novolak photoresist compositions
Assignee: Olin Microelectronic Chemicals Inc
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Filing: 1981-06-22
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Granted: 1983-03-22
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Expires: 2001-06-22
Abstract
Abstract Fast positive photoresist compositions employing cresol-formaldehyde novolak resins made from a mixture containing meta- and paracresol or ortho-, meta- and paracresol in a ratio selected from a given range and one or more of a selected group of naphthoquinone diazide sensitizing compounds. When dissolved in a mixture of organic solvents, the photoresist compositions are suitable for application as a thin coating to a substrate. After the coating has been dried, the coated substrate can be exposed to image-wise modulated actinic radiation even in the deep ultra-violet range and developed in alkaline solution, yielding a high-resolution relief pattern of resist on substrate useful for a number of applications.
Inventors
- 👤 Medhat A. Toukhy
- 👤 Leo Klawansky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:45
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/023; G03F7/0233; G03F7/0236; C; C08; C08G; C08G8/00; C08G8/04; C08G8/08; C08G8/24; C08K; C08K5/00; C08K5/36; C08K5/41
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
102 words
A positive photoresist composition, comprising a mixture of: (a) about 80 to 99 percent by weight of a cresolformaldehyde novolak resin produced by condensing a mixture of cresol isomers with formaldehyde in the presence of acid, said mixture of cresols including percentages by weight of ortho-, meta-, and paracresols whose values are within the area bounded by quadrilateral ABCD in FIG. 1, said novolak resin having a softening point in the range of 110° to 145° C.; and (b) about 1 to 20 percent by weight of at least one napthoquinone diazide sensitizer selected from the group consisting of: ##STR5## wherein ##STR6##
Claim 2
Dependent Claim
102 words
A positive photoresist composition, comprising a mixture of: (a) about 80 to 99 percent by weight of a cresolformaldehyde novolak resin produced by condensing a mixture of cresol isomers with formaldehyde in the presence of acid, said mixture of cresols including percentages by weight of ortho-, meta-, and paracresols whose values are within the area bounded by quadrilateral ABCD in FIG. 1, said novolak resin having a softening point in the range of 110° to 145° C.; and (b) about 1 to 20 percent by weight of at least one napthoquinone diazide sensitizer selected from the group consisting of: ##STR5## wherein ##STR6##
Claim 3
Dependent Claim
25 words
A positive photoresist composition suitable for application to a substrate, comprising a mixture as set forth in claim 1 and at least one organic solvent.
Claim 4
Dependent Claim
29 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the molar ratio of formaldehyde to cresols reacted to produce the novolak does not exceed 0.9:1.
Claim 5
Dependent Claim
27 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 47 percent metacresol and 53 percent paracresol by weight.
Claim 6
Dependent Claim
30 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 47 percent metacresol, 40 percent paracresol and 13 percent orthocresol by weight.
Claim 7
Dependent Claim
30 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 62 percent metacresol, 5 percent paracresol and 33 percent orthocresol by weight.
Claim 8
Dependent Claim
27 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 95 percent metacresol and 5 percent paracresol by weight.
Claim 9
Dependent Claim
27 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 50 percent metacresol and 50 percent paracresol by weight.
Claim 10
Dependent Claim
30 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 70 percent metacresol, 20 percent paracresol and 10 percent orthocresol by weight.
Claim 11
Dependent Claim
30 words
A positive photoresist composition, as set forth in claims 1 or 2, wherein the mixture of cresols comprises 50 percent metacresol, 37.5 percent paracresol and 12.5 percent orthocresol by weight.
References Cited (Backward Citations)
US3130048A
Cited
GB1154749A
Cited
GB1227602A
Cited
US3647443A
Cited
US3666473A
Cited
DE2616992A1
Cited
US4173470A
Cited
US4211834A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-21 | 1986-09-20 | 1987-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-21 | 1990-09-20 | 1991-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-21 | 1994-09-20 | 1995-03-22 | $7700.00 | Window Closed / Lapsed |