Properties and mutual interactions of various acrylate monomers used in 193 nm resists

Both the physical and chemical properties of various acrylate monomers, typically used in polymer matrices for 193 nm lithography, are investigated. The influence of each monomer on the glass transition temperature (Tg) of the final polymer is determined. The high Tg values measured for the different polymers lead to the conclusion that most acrylate based formulations tend to be non-annealing type resists. Mutual chemical interactions between monomers are also demonstrated. These phenomena underline the limits of the introduction of alicyclic ester groups in acrylic polymers and the complexity of the mechanisms involved in these resists.