Synthesis and lithographic characterization of poly[(dihydrocarveol)-co-(1,1-dimethylethyl bicyclo[2.2.1]hept-5-ene-2-carboxylate)-co-(maleic anhydride)]

A new ArF single-layer resist polymer, poly(dihydrocarveol-co-1,1-dimethylethyl bicyclo2.2.1]hept-5-ene-2-carboxylate-co-maleic anhydride) has been synthesized by radical polymerization. The molar composition of synthesized resist polymer was confirmed by elemental analysis. The obtained molar composition was 0.25:0.35:0.40. This resist polymer was found to be stable up to 230 °C, but above 250 °C it underwent rapid thermal deprotection of the tert-butyl groups by releasing carbon dioxide and 2-methylpropene. The deprotection temperature was established by DSC and TGA. Using the resist, 0.14 µm L/S pattern was obtained at 26 mJ/cm⁻² doses, using an ArF stepper and the developer of 2.38 wt% tetramethyl ammonium hydroxide aqueous solution. © 1999 Society of Chemical Industry