SYNTHESIS AND PHOTORESIST PROPERTY OF A POLYAMIDE CONTAINING A NAPHTHYLUREA MOIETY

A novel polyamide containing a naphthylurea moiety as the photoreactio n site (NpUrea-PA) was synthesized by polycondensation of N-3,5-dicarb oxyphenyl-N'-1-naphthylurea and 4,4'-oxydianiline (ODA). The model rea ctions, which consisted of irradiation by UV light of the low molecula r weight aromatic ureas and isocyanate, suggested that the photochemis try involves an aromatic isocyanate intermediate. NpUrea-PA acts as th e negative working resist, by UV irradiation through a quartz mask fol lowed by development using aprotic solvents such as N,N-dimethylacetam ide (DMAc). The contrast of the negative tone image was improved by us ing 20 wt% of p-xylylenediamine (pXDA) as a crosslinking agent.