Sensitivity improvement of fluoroalkylated EUV resist with electron-rich vinyl units

In this study, we present a method to enhance the sensitivity of fluorinated EUV resists by leveraging the rapid coupling reaction between electrophilic carbon radicals and electron-rich alkenes. To validate the impact of the vinyl groups, DVS-HNF was synthesized by introducing fluorinated alkyl chains and silyl vinyl functional groups into the model compound. Additionally, TMS-HNF and EDMS-HNF, which do not contain a vinyl moiety, were synthesized for comparison. To evaluate the patterning properties of the three materials, e-beam lithography experiments were conducted, resulting in the formation of negative-tone patterns for all three materials. Comparing sensitivities, DVS-HNF with two vinyl moieties exhibited the most excellent sensitivity, confirming the effective collaboration between fluorinated alkyl radicals and vinyl groups. After performing an EUV lithography experiment on DVS-HNF, it was confirmed that a 30 nm negative-tone pattern was successfully formed with excellent sensitivity. These results substantiate the potential of the single-component molecular resist for high performance EUV lithography.