Design of a disulfide bond-containing photoresist with extremely low volume shrinkage and excellent degradation ability for UV-nanoimprinting lithography

Abstract

UV-nanoimprinting lithography has the merits of high throughput and resolution, low cost of manufacture and room temperature operation, and thus finds wide applications in various fields. Herein, a novel disulfide bond-containing photoresist for UV nanoimprint lithography was designed and prepared based on the disulfide compound, 2,2-dithiodiethanol diacrylate (DTDA), isobornyl acrylate (IBOA) and methyl methacrylate (MMA). The addition of DTDA could obviously enhance the double bond conversion (97%), polymerization rate (19% s−1) and thermal stability of the photoresist, but slightly reduce the Young’s modulus and indentation hardness. Remarkably, the as-prepared photoresist exhibited very low volume shrinkage that was as low as 0.93% owing to the reversible nature of the disulfide bond under UV light irradiation. Meanwhile, it had an excellent degradation ability in the presence of tributyl phosphine (TBP) and easily was removed from the mold. More importantly, the photoresist manifested an outstanding pattern transfer ability and could precisely duplicate the pattern with the line width of 206 nm and the height of 108 nm in the quartz mold without distortion.