Patent US4606999A successfully refreshed from Google Patents.
US4606999A
Expired / Lapsed
US
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Development of positive photoresists using cyclic quaternary ammonium hydroxides
Assignee: ATK Launch Systems LLC
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Filing: 1985-11-12
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Granted: 1986-08-19
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Expires: 2005-11-12
Abstract
Abstract A method of developing a positive photoresist layer which has been image-wise-exposed comprising contacting the layer with an alkaline developing composition to remove exposed areas of the layer, the developing composition comprising a solution containing a cyclic quaternary ammonium hydroxide developing agent in a sufficient concentration to remove exposed areas of the layer. The present invention also includes a developing composition for use in the method.
Inventors
- 👤 Susan B. Poulin
- 👤 Ann B. Salamone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:47
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/30; G03F7/32; G03F7/322
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
102 words
A method of developing a positive photoresist layer of the novalac type which has been image-wise-exposed to radiation comprising contacting the layer with an alkaline developing composition to remove exposed areas of the layer, the developing composition consisting essentially of a solution of a cyclic quaternary ammonium hydroxide developing agent in which a quaternary substituted nitrogen is a member of an aromatic or nonaromatic ring between 4 and 8 atoms, said developing agent being present in a concentration sufficient to act as a developing agent, the solution having a normality of the cyclic quaternary ammonium hydroxide between about 0.1N and about 6.0N.
Claim 2
Independent Claim
102 words
A method of developing a positive photoresist layer of the novalac type which has been image-wise-exposed to radiation comprising contacting the layer with an alkaline developing composition to remove exposed areas of the layer, the developing composition consisting essentially of a solution of a cyclic quaternary ammonium hydroxide developing agent in which a quaternary substituted nitrogen is a member of an aromatic or nonaromatic ring between 4 and 8 atoms, said developing agent being present in a concentration sufficient to act as a developing agent, the solution having a normality of the cyclic quaternary ammonium hydroxide between about 0.1N and about 6.0N.
Claim 3
Dependent Claim
66 words
The method of claim 1 wherein the cyclic quaternary ammonium hydroxide is a derivative of pyridine, purine, pyrrole, carbazole, an isopyrrole, diazepine, pyrazole, azepine, triazole, indole, oxazole, indolemine, isoxazole, isobenzazole, thiazole, pyrindine, an isothiazole, pyranol-pyrrole, an oxadiazole, isoindazole, dioxazole, indoxazine, pyridazine, benzoxazole, pyrimidine, anthranil, pyrazine, quinoline, piperazine, isoquinoline, triazine, cinnoline, oxazine, quinazoline, isoxazine, naphthridine, oxathiazine, pyrido-pyridine, oxadiazine, benzoxazine morpholine, benzisoxazine, acridine, imidazoline, an oxatriazole, or pyrrolidone.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein the quaternary nitrogen of the cyclic quaternary ammonium hydroxide is within an aromatic ring.
Claim 5
Dependent Claim
17 words
The method of claim 3 wherein the cyclic quaternary ammonium hydroxide is an N-alkyl substituted pyridinium hydroxide.
Claim 6
Dependent Claim
20 words
The method of claim 4 wherein the alkyl group on the quaternary nitrogen is of one of four carbon atoms.
Claim 7
Dependent Claim
15 words
The method of claim 4 wherein the cyclic quaternary ammonium hydroxide is N-methyl pyridinium hydroxide.
Claim 8
Dependent Claim
23 words
The method of claim 1 wherein the normality of the developing agent within the developing composition is between about 0.2N and about 0.5N.
Claim 9
Dependent Claim
17 words
The method of claim 1 wherein the developing composition comprises an aqueous solution of the developing agent.
Claim 10
Dependent Claim
13 words
The method of claim 1 wherein the developing composition also includes a surfactant.
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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) | 1989-08-18 | 1990-02-17 | 1990-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-18 | 1994-02-17 | 1994-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-18 | 1998-02-17 | 1998-08-19 | $7700.00 | Window Closed / Lapsed |