THEORETICAL CALCULATIONS OF SENSITIVITY OF DEPROTECTION REACTIONS FORACRYLIC POLYMERS FOR 193 NM LITHOGRAPHY II - PROTECTION GROUPS CONTAINING AN ADAMANTYL UNIT

The reaction energy of deprotection reactions, glass transition temper ature, and the dielectric constant were calculated for photoresists ha ving a 2-alkyl-2-adamantyl group. It was found that the lower sensitiv ity of the polymer with a 2-methyl-2-adamantyl group (compared with th e sensitivities of the polymers with a 2-ethyl-2-adamantyl group and a 2-butyl-2-adamantyl group) can be attributed to the smaller exothermi c (or greater endothermic) reaction energy of its deprotection reactio n. It was also found that the sensitivity difference between the polym ers with the 2-ethyl-2-adamantyl and 2-butyl-2-adamantyl groups can be attributed to the difference in the calculated dielectric constant, w here a higher dielectric constant leads to a higher sensitivity.