Synthesis and characterization of alicyclic polymers with hydrophilic groups for 193 nm single-layer resist

A novel substituted alicyclic polymer for a 193 nm resist has been developed. The goal uas to enhance the adhesion to Si substrates while ensuring compatibility with a tetramethylammonium hydroxide (TMAH) developer for our polyolefin resist. We designed alicyclic polymers including hydrophilic groups to improve the adhesion property. The hydrophilicity of the hydroxy group affords good adhesion of the formulated resist patterns to Si substrates. We have synthesized an ArF polymer resin, poly(2-hydroxyethyl 5-norbornene-2-carboxylate/t-butyl 5-norburnene-2-carboxylate/5-norborne-2,3-dicarboxylic acid/maleic anhydride), in which all of the main chains are composed of alicyclic units. 2-Hydroxyethyl 5-norbornene-2-carboxylate and 5-norbornene-2,3-dicarboxylic acid were found to be very suitable adhesion and sensitivity promoters, respectively. A 0.12 mu m US (lines/spaces) pattern was obtained at 14 mJ/cm(2) doses, using an ArF stepper on the developer and 2.38 wt% TMAH aqueous solution.