Abstract
Acrylate monomers were synthesized using a novel aerobic oxidation reaction employing N-hydroxyphtalimide (NHPI) as a catalyst, and then polymerized. These reactions were confirmed to be applicable for the mass production of those compounds. We have synthesized series of reported 193-nm resist materials, and found that they are subject to certain problems. That is, acrylates having hydrophilic acid leaving groups, such as pyranyl or acid-leaving lactones usually have poor etching resistance. Moreover, t-butyl acid-leaving groups or acid-leaving alicyclic groups are too hydrophobic to achieve high performance of the resist. From this point of view, we have designed and synthesized advanced monomers having hybrid structure of alicyclic ring and polar moiety, using aerobic oxidation reaction Finally, patterns with a resolution of 0.13-micron, based on the 1G bit DRAM design rule, were successfully fabricated by optimizing the resist composition containing newly synthesized monomers.
