Process for forming a photoresist pattern by top surface imaging process

A process for forming a photoresist pattern comprising the steps of:

• (a) preparing a chemical amplification photoresist composition comprising a cross-linker, a photoacid generator and a photoresist polymer in a solvent;
• (b) coating the photoresist composition on a substrate of a semiconductor element to form a photoresist film;
• (c) exposing the photoresist film to light;
• (d) performing a silylation process on the photoresist film to form a silicon oxide film pattern on the surface of the exposed photoresist film;
• (e) developing the photoresist film to form a pattern thereon;
• and
• (f) etching the substrate using the silicon oxide film pattern as an etching mask;
• wherein the cross-linker contained in the photoresist composition comprises at least one compound selected from the group consisting of monomers represented by the following Chemical Formulas 1 and 2 and polymers thereof:
• wherein, R1 and R2 individually represent straight or branched C1-10 alkyl, straight or branched C1-10 ester, straight or branched C1-10 ketone, straight or branched C1-10 carboxylic acid, straight or branched C1-10 acetal, straight or branched C1-10 alkyl including at least one hydroxyl group, straight or branched C1-10 ester including at least one hydroxyl group, straight or branched C1-10 ketone including at least one hydroxyl group, straight or branched C1-10 carboxylic acid including at least one hydroxyl group, and straight or branched C1-10 acetal including at least one hydroxyl group;
• and R3 represents hydrogen or methyl;
• wherein,
• R represents straight or branched C1-10 alkylene optionally comprising a functional group selected from the group consisting of an ester, ketone, carboxylic acid, acetal, hydroxyl, and combinations thereof;
• each of R5 and R6 is independently hydrogen, straight or branched C1-10 alkyl, straight or branched C1-10 ester, straight or branched C1-10 ketone, straight or branched C1-10 carboxylic acid, straight or branched C1-10 acetal, straight or branched C1-10 alkyl including at least one hydroxyl group, straight or branched C1-10 ester including at least one hydroxyl group, straight or branched C1-10 ketone including at least one hydroxyl group, straight or branched C1-10 carboxylic acid including at least one hydroxyl group, and straight or branched C1-10 acetal including at least one hydroxyl group;
• R7 represents hydrogen or methyl;
• m represents 0 or 1;
• and
• n represents a number of 1 to 5.