DISSOLUTION INHIBITORS FOR 193-NM CHEMICALLY AMPLIFIED RESISTS

Dissolution characteristics and adhesion of 193-nm resists have been i nvestigated by using molecular orbital calculations. The calculation i ndicated that naphthalene compound had better adhesion than alicyclic compounds by a factor of 1.2. Another calculation result obtained indi cated that naphthalene was more hydrophilic than alicyclic compounds. In order to improve the adhesion and dissolution characteristics of th e alicyclic resist; introduction of the naphthalene backbone into alic yclic resists was attempted in the form of additives (dissolution inhi bitors) or copolymer components. Dissolution inhibitors that have simu ltaneously a naphthol novolak backbone and a characteristic generate c arboxylic acid, such as tetrahydropyranyl ester of naphthol novolak co mpound condenced with glyoxlic acid (NV4THP), were the most effective dissolution inhibitors increasing dry etch resistance of base polymer by 14% and pattern resolution of original resist by 10%. The naphthale ne dissolution inhibitor also largely improves pattern adhesion. These results were consistent with above-mentioned calculation results. 193 -nm resists containing vinyl naphthalene in the copolymer structure we re also investigated and fundamental resist requirements were satisfie d with this polymer by adding adamantane dissolution inhibitor di-tert -butyl 2-((1-adamanthyl)carbonylmethyl) malonate (ADTB).