Radiation stability of cations in ionic liquids. 4. Task-specific antioxidant cations for nuclear separations and photolithography.
Three families of "task-specific" antioxidant organic cations that include designated sites to facilitate deprotonation following electronic excitation and ionization have been introduced. The deprotonation from the excited state is reversible, leading to minimal damage of the cation, whereas the deprotonation from the oxidized cation yields persistent aroxyl and trityl radicals. This protection improves radiation stability of ionic compounds in 2.5 MeV electron beam radiolysis. Apart from the use of such cations as structural components of room temperature ionic liquid (IL) diluents for nuclear separations, their ionic compounds involving bases of superacids are well suited for use as chemically amplified acid generator resists in electron beam lithography and extreme ultraviolet photolithography.
Chemical Sciences and Engineering Division, Argonne National Laboratory , 9700 South Cass Avenue, Argonne, Illinois 60439, United States.
Ilya A
IA
Shkrob
Timothy W
TW
Marin