Improvement of dual insolubilization resist performance through the incorporation of various functional units

摘要

The acid diffusion in chemically amplified resists (a current standard resist for semiconductor device manufacturing) is asignificant concern in the development of highly resolving resists. However, non-chemically amplified resists (non-CARs) are generally less sensitive to radiation than CARs due to lack of amplification mechanism. Recently, a negativetypenon-CAR resist utilizing polarity change and radical crosslinking (a dual insolubilization resist) was proposed. Inthis study, an acid reactive compound was introduced into the organotin-containing dual insolubilization resists toimprove their sensitivity. The synthesized resists were composed of triarylsulfonium cations as a polarity changer andradical generator, 2,2,2-trisubstituted acetophenone as a radical generator, triphenyl(4-vinylphenyl)stannane (TPSnSt) asan EUV absorption enhancer and a quencher, and 4-[(2,4-Dimethoxyphenyl)hydroxymethyl]phenylmethacrylate(ARMA) as a polymer-bound acid-reactive unit. By the incorporation of ARMA, the sensitivity to extreme ultraviolet(EUV) radiation was increased by 2.4 times (the exposure dose for insolubilization was decreased by approximately60%). The sensitivity enhancement is considered to have been caused by the acid catalytic etherification of ARMAthrough dimerization and/or with 2,2,2-trisubstituted acetophenone units.