Synthesis and Lithographic Characterization of Poly(5-vinyluracil) Derivative

Enol ether derivative of poly(5-vinyluracil) released completely the tert-butyl groups above 195 °C and gave poly(5-vinyluracil). The resist film as spin coated from chloroform solution containing photo-acid generator released completely the tert-butyl groups after UV light (250 nm) irradiation followed by post exposure baking. Solubility of the obtained polymer containing uracil unit was significantly different from the original polymer containing alkoxy units in both polar (TMAH aq for negative) and nonpolar (anisole for positive) solvents as developer. The results were compared with values of the poly(6-vinyluracil) derivative, and the difference were attributable to the difference of the polymer structures.