Acid Quantum Efficiency of Anion-bound Chemically Amplified Resists upon Exposure to Extreme Ultraviolet Radiation

抄録

EUV lithography is one of candidates for the high-volume manufacturing of semiconductor devices with sub-10 nm critical dimension. An anion-bound polymer, in which the anion part of onium salts is introduced into main chain polymer, has attracted much attention for sub-10 nm fabrication. We have modeled the acid generation of anion-bound resists and developed a simulation code for facilitating the development and improvement of resist materials and processes for EUV lithography [1]. In this study, the acid quantum efficiency of acid generation was investigated using the developed simulation code. The quantum efficiency did not depend on the thermalization distance. The increase in the efficiency of acid generation from an electronically excited state of the resist and the suppression of the reaction between phenyl radicals are important for the improvement of quantum efficiency.