The present invention relates to a cross-
linker for 
photoresist compositions which is suitable for a 
photolithography process using KrF (248 mn), ArF (193 mn), E-beam, 
ion beam or EUV light sources. Preferred cross-linkers, according to the present invention, comprise a 
copolymer of (i) a compound represented by following 
Chemical Formula 1 and / or (ii) one or more compound(s) selected from the group consisting of 
acrylic acid, 
methacrylic acid and 
maleic anhydride. ##STR1## wherein, R.sub.1 and R.sub.2 individually represent straight or branched C.sub.1-10 
alkyl, straight or branched C.sub.1-10 ester, straight or branched C.sub.1-10 
ketone, straight or branched C.sub.1-10 
carboxylic acid, straight or branched C.sub.1-10 
acetal, straight or branched C.sub.1-10 
alkyl including at least one hydroxyl group, straight or branched C.sub.1-10 ester including at least one hydroxyl group, straight or branched C.sub.1-10 
ketone including at least one hydroxyl group, straight or branched C.sub.1-10 
carboxylic acid including at least one hydroxyl group, and straight or branched C.sub.1-10 
acetal including at least one hydroxyl group; and R.sub.3 represents 
hydrogen or methyl.