Patent US4142892A successfully refreshed from Google Patents.
US4142892A
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US
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Method of reducing the defect density in a positive-working photoresist layer using a salt of imidazolinium
Assignee: International Business Machines Corp
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Filing: 1977-05-20
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Granted: 1979-03-06
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Expires: 1997-05-20
Abstract
Abstract The density of defects formed during the exposure of a positive resist layer, due to the loss of photoresist in circular areas is reduced by the addition of an antistatic agent. The resist layer includes a phenol-formaldehyde resin and an o-diazoquinone photoactive compound and a suitable antistatic agent is a 2-alkyl-N-hydroxyethyl imidazolinium salt.
Inventors
- 👤 Gabor Paal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:23
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/85; A; A61; A61K; A61K8/00; A61K8/18; A61K8/72; A61K8/73; A61K8/736; A61Q; A61Q5/00; A61Q5/06; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/0226
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
118 words
In a process for forming a resist mask, in which a positive working photoresist layer comprising a phenol-formaldehyde novolak resin and a photosensitive o-diazoquinone sulfonic acid ester, is patternwise exposed to actinic radiation and the exposed portion is removed by an aqueous alkaline developer, the improvement which comprises: reducing the defect density caused by the loss of resist during exposure by including in said layer, prior to exposing the layer, an effective amount of a compound of the general formula: ##STR2## where R 1 is a hydroxyethyl group, R 2 is an alkyl group with 7 to 17 carbon atoms, and X - is an acid anion selected from the group consisting of acetate, oleate, stearate, and p-toluol-sulfonate.
Claim 2
Dependent Claim
118 words
In a process for forming a resist mask, in which a positive working photoresist layer comprising a phenol-formaldehyde novolak resin and a photosensitive o-diazoquinone sulfonic acid ester, is patternwise exposed to actinic radiation and the exposed portion is removed by an aqueous alkaline developer, the improvement which comprises: reducing the defect density caused by the loss of resist during exposure by including in said layer, prior to exposing the layer, an effective amount of a compound of the general formula: ##STR2## where R 1 is a hydroxyethyl group, R 2 is an alkyl group with 7 to 17 carbon atoms, and X - is an acid anion selected from the group consisting of acetate, oleate, stearate, and p-toluol-sulfonate.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein 2-alkyl-N-hydroxyethyl-imidazolinium acetate is added to the photoresist composition.
Claim 4
Dependent Claim
22 words
The method of claim 1, wherein the compound is added in a quantity of about 1% by weight of the photoresist composition.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |