Oxabicyclo compound, a polymer-containing said compound, and a photoresist micro pattern forming method using the same

A method of preparing a photoresist copolymer of the following Formula 2:

• ##STR41## wherein, X is 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 2-hydroxybutyl, 3-hydroxybutyl, 2-methyl-3-hydroxypropyl or 4-hydroxybutyl;
• Y is a hydrogen or a carboxylic acid group;
• and a, b, c and d are the respective polymerization ratios of co-monomers having a part in the copolymerization;
• comprising the steps of:
• (a) dissolving in a polymerization organic solvent (i) one or more compounds selected from the group consisting of t-butyl 5-norbornene-2-carboxylate;
• 5-norbornene-2-carboxylic acid and 5-norbornene-2,3-dicarboxylic acid;
• (ii) maleic anhydride;
• and (iii) the compound represented by the following Formula 1:
• ##STR42## wherein, R.sub.1 and R.sub.2 are the same or different, and represent a hydrogen or a C.sub.1 -C.sub.4 straight or branched chain substituted alkyl group;
• and m is a number from 1 to 4;
• and
• (b) adding a polymerization initiator to the resultant solution;
• (c) precipitating the resultant solution using an ethyl ether solvent.