US Patent 10520809 Resist composition and patterning process

A resist composition comprising a base polymer and a metal salt of an iodinated aromatic group-containing carboxylic acid, the metal being selected from among sodium, magnesium, potassium, calcium, rubidium, strontium, cesium, barium, cobalt, nickel, copper, zinc, cadmium, tin, antimony, zirconium, hafnium, cerium, aluminum, and indium, exhibits a sensitizing effect and an acid diffusion suppressing effect and forms a pattern having improved resolution, LWR and CDU.