A new ArF matrix based on poly(vinylsulfonamide) has been developed. Sulfonamides, whose <i>p</i>Ka values are comparable to those of phenols, can be used as acidic functional groups in the design of chemically amplified resist (CAR) and aqueous base developable resist. Various poly(<i>N</i>-alkyl vinylsulfonamide)s were prepared (R=H, CH<sub>2</sub>CF<sub>3</sub>, Pr, 1-adanmantyl), and showed high transparency at round 193 nm region. Depending on the substituents, the dissolution rates of films in a 2.38 wt% aqueous tetraethylammonium hydroxide solution were varied from 500 to 0.0035 nm/s. The tetrahydropyranyl (THP) protected poly(vinylsulfonamide) was prepared and the deprotection of THP was easily occurred when the photoresist containing a photoacid generator was exposed to UV light, followed by post-exposure baking.