Method for producing copolymer for semiconductor lithography containing reduced amount of metal impurities, and method for purifying polymerization initiator for production of copolymer
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jan 17, 2017
Grant Date -
Jan 28, 2016
app pub date -
Oct 7, 2015
filing date -
Apr 21, 2011
priority date (Note) -
In Force
status (Latency Note)
Importance
Abstract
A method for producing a copolymer for semiconductor lithography containing less metal impurities, and a method for purifying a polymerization initiator for production of the copolymer, are provided. The method for purifying a polymerization initiator to be used for production of a polymer includes a filtering step wherein a solution of a polymerization initiator dissolved in an organic solvent is allowed to pass through a filter having a nominal pore size of not more than 1.0 μm, to reduce the sodium content of the polymerization initiator solution to not more than 300 ppb with respect to the weight of the polymerization initiator. Further, the method for producing a copolymer for semiconductor lithography includes a polymerization step wherein the polymer for semiconductor lithography is synthesized by a radical polymerization reaction in the presence of a polymerization initiator purified by the above purification method.
First Claim
Family
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully