Patent EP0251187A2 successfully refreshed from Google Patents.
EP0251187A2
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Method for purifying novolak resins useful as material for coating on a semiconductor substrate
Assignee: Zeon Corp
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Filing: 1987-06-24
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Granted: —
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Expires: 2007-06-24
Abstract
Abstract A method of purifying novolak resins useful as a material for coating on a semiconductor substrate, which comprises dissolving a novolak resin in a solvent having a solubility in water at 20 DEG C of not more than l00, and extracting the resulting solution with an acidic aqueous solution thereby to reduce the metal content of the resin. If desired, the solution may be subjected to both the extraction step and a centrifugal separation step in a desired sequence instead of the extraction step alone.
Inventors
- 👤 Sadao C/O Gijutsukaihatsu Center Of Sugimoto
- 👤 Teturiyo C/O Gijutsukaihatsu Center Of Kusunoki
- 👤 Mikio C/O Gijutsukaihatsu Center Of Yajima
- 👤 Nobukazu C/O Gijutsukaihatsu Center Of Takahashi
- 👤 Katsuhiro Fujino
- 👤 Hiroshi Yano
- 👤 Shuzo Fujimura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 17:30
CPC Classifications
H; H05; H05K; H05K3/00; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/36; C; C08; C08G; C08G8/00; C08G8/04; C08G8/08; C08G8/12; G; G03; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/023; G03F7/0233; G03F7/0236
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
66 words
l A method of purifying a novolak resin useful as a material for coating on a semiconductor substrate, which comprises dissolving the novolak resin in a solvent having a solubility in water at 20°C of not more than l00, and extracting the resulting solution with an acidic aqueous solution having a pH of not more than 3, thereby to reduce the metal content of the resin.
Claim 2
Independent Claim
28 words
The method of claim l wherein the solvent is selected from the group consisting of acetates, ketones, alcohols, glycol ether acetates, halogenated hydrocarbons, ethers, ligroin and solvent naphtha.
Claim 3
Independent Claim
21 words
The method of claim l wherein the material for coating on a semiconductor substrate is a resist or a flattening material.
Claim 4
Independent Claim
76 words
A method of purifying a novolak resin useful as a material for coating on a semiconductor substrate, which comprises dissolving the novolak resin in a solvent having a solubility in water at 20°C of not more than l00, and thereafter subjecting the resulting solution in any desired sequence to liquid-liquid extraction with an acidic aqueous solution having a pH of not more than 3 and centrifugal separation, thereby to reduce the metal content of the resin.
Claim 5
Dependent Claim
28 words
The method of claim 4 wherein the solvent is selected from the group consisting of acetates, ketones, alcohols, glycol ether acetates, halogenated hydrocarbons, ethers, ligroin and solvent naphtha.
Claim 6
Dependent Claim
21 words
The method of claim 4 wherein the material for coating on a semiconductor substrate is a resist or a flattening material.
Claim 7
Dependent Claim
22 words
Use of the purified novolak resin obtained by the method of claim l as a material for coating on a semiconductor substrate.
Claim 8
Dependent Claim
22 words
Use of the purified novolak resin obtained by the method of claim 4 as a material for coating on a semiconductor substrate.
References Cited (Backward Citations)
No citation records indexed.
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