Disruptive non-fluorinated photoacid generators using computational chemistry and library design

Abstract

Per- and polyfluoroalkyl substances (PFAS) have been identified by various regulatory bodies as substances of concern. In line with the objective of safer and sustainable by design, a comprehensive program has been initiated to address these concerns. Part of this program includes the development of non -fluorinated photoacid generators (PAGs) without introducing new chemicals with unintended consequences. Using computational chemistry and synthetic organic chemistry, several scaffolds amenable to PAG library design have been realized. These novel PAGs offer facile tunability and advantages in many critical design parameters such as pKa, diffusion, absorption, shelf-life stability, and scalability. These early generation non-fluorinated PAGs show competitive and similar lithographic performance compared to fluorinated PAGs in i-line, krypton fluoride (KrF) laser, argon fluoride (ArF) laser and extreme ultraviolet (EUV) lithography.