A sulfonic acid anion-containing polymer having an alkylsulfonium cation not in covalent bond thereto can be readily prepared by reacting a sulfonic acid anion-containing polymer having an ammonium or metal cation with an alkylsulfonium salt under mild conditions. A resist composition comprising the inventive polymer is effective for suppressing acid diffusion since the sulfonium salt is bound to the polymer backbone. When processed by the ArF lithography, the polymer exhibits a lower absorption at the exposure wavelength than the triarylsulfonium salt form PAGs, resulting in improved resolution, mask fidelity, and LWR.
将具有
铵或
金属阳离子的含
磺酸阴离子聚合物与烷基锍盐在温和的条件下进行反应,可以很容易地制备出具有非共价键烷基锍阳离子的含
磺酸阴离子聚合物。由于锍盐与聚合物骨架结合,因此包含本发明聚合物的抗蚀剂组合物能有效抑制酸扩散。用 ArF 光刻技术处理时,该聚合物在曝光波长处的吸收率低于三芳基锍盐形式的 PAG,从而提高了分辨率、掩模保真度和低温再生率。