Dry etch stability

To address these shortcomings the carboxylic acid was replaced with weaker phenol for a better shelf life and dry etch stability and the vinyl ether functionality was separated from the acidic functionality employing a three component design. A water soluble phenolic copolymer was prepared by radical copolymerization of 4-acetoxystyrene and sodium styrenesulfonate, followed by deacetylation with ammonium hydroxide. A water soluble bis(vinyl ether)... 

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