Patent US4576903A successfully refreshed from Google Patents.
US4576903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developer for positive photoresists
Assignee: Novartis Corp
•
Filing: 1984-12-21
•
Granted: 1986-03-18
•
Expires: 2004-12-21
Abstract
Abstract A developer suitable for use with positive photoresists is based on a buffered aqueous-alkaline solution containing non-ionic surfactants and contains in the solution 1-100 ppm of the surfactants, preferably of the ethoxylated-alkylphenol type. The resultant photoresist shows outstanding properties with respect to the resolution and edge sharpness obtainable in the developed resist image and with respect to its developing activity, developing capacity and stability.
Inventors
- 👤 Winfried Baron
- 👤 Kurt Marquard
- 👤 Hans-Joachim Merrem
- 👤 Raimund Sindlinger
- 👤 Klaus-Peter Thiel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:27
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/26; G03F7/30; G03F7/32; G03F7/322
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
72 words
In a developer for positive photoresists of the phenol/formaldehyde-novolak type containing an o-diazoquinone-type compound as a light-sensitive component, consisting essentially of effective amounts of, water, an inorganic alkali metal compound producing hydroxyl ions in water, a buffer maintaining a pH of about 12-14, and a non-ionic surfactant, the improvement wherein the amount of non-ionic surfactant is about 1-100 ppm, whereby said developer is effective to develop said positive photoresist with high resolution.
Claim 2
Dependent Claim
72 words
In a developer for positive photoresists of the phenol/formaldehyde-novolak type containing an o-diazoquinone-type compound as a light-sensitive component, consisting essentially of effective amounts of, water, an inorganic alkali metal compound producing hydroxyl ions in water, a buffer maintaining a pH of about 12-14, and a non-ionic surfactant, the improvement wherein the amount of non-ionic surfactant is about 1-100 ppm, whereby said developer is effective to develop said positive photoresist with high resolution.
Claim 3
Dependent Claim
13 words
A developer according to claim 1, which contains 10-60 ppm of the surfactant.
Claim 4
Dependent Claim
13 words
A developer according to claim 1, which contains 30-50 ppm of the surfactant.
Claim 5
Dependent Claim
13 words
A developer according to claim 1, wherein the surfactant is an ethoxylated alkylphenol.
Claim 6
Dependent Claim
24 words
A developer of claim 1 wherein the non-ionic surfactant is an ethoxylated (C 6-14 -alkyl)phenol of a degree of ethoxylation of 2 to 20.
Claim 7
Dependent Claim
13 words
A developer of claim 5 wherein the degree of ethoxylation is about 9.
Claim 8
Dependent Claim
20 words
A developer of claim 4 wherein the alkali metal compound is a silicate, a metasilicate, a phosphate or a hydroxide.
Claim 9
Dependent Claim
17 words
A developer of claim 7 wherein the amount of alkali metal compound is about 1-6% by weight.
Claim 10
Dependent Claim
13 words
A developer of claim 8 wherein the alkali metal compound is a metasilicate.
Claim 11
Dependent Claim
15 words
A developer of claim 1 wherein the pH maintained by the buffer is about 12.5-13.5.
Claim 12
Dependent Claim
17 words
A developer of claim 1 consisting of water, said alkali metal compound, said buffer and said surfactant.
References Cited (Backward Citations)
US3586504A
Cited
US4147545A
Cited
US4053314A
Cited
US4001133A
Cited
US4212902A
Cited
US4263392A
Cited
US4374920A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-17 | 1989-09-16 | 1990-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-17 | 1993-09-16 | 1994-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-17 | 1997-09-16 | 1998-03-18 | $7700.00 | Window Closed / Lapsed |