Role of resist components in electron emission and capture

In extreme ultraviolet (EUV) resists, due to the high energy of the incident photons, most of the radiation chemistry arises from the emitted electrons and not the EUV photons themselves. The absorption of an EUV photon by a resist film leads to the emission of primary electrons, which, through a cascade of inelastic scattering events, cause excitation of molecules and emission of secondary electrons. Because the electrons are playing a leading role in EUV patterning by initiating the majority of chemical transformations, it is important to characterize their generation, transport, and energy distribution. In this work we investigate the emission of electrons in model EUV photoresists using photoelectron spectroscopy. The photoelectron spectroscopy reveals variations in the energy distributions and abundances of emitted electrons for different resist compositions ( bare polymer, PAG, and quencher concentrations). EUV exposure of resists induces a change of the electron emission spectra, mostly affecting emission of slow secondary electrons. By applying this approach to each resist component, we begin to decipher the role of resist components in electron generation, capture, and transmission.