Investigating EUV radiochemistry with condensed phase photoemission

In EUV, photoelectrons and secondary electrons play indispensable roles in the chemistry of photoresist. An accurate understanding of electron related processes provides foundation for targeted engineering of resists and other EUV materials. As chemistry is initiated by secondary electrons, acquiring the electron energy distribution inside an actual photoresists is important for improving the efficiency of chemical activation. We demonstrate that condensed phase photoemission spectroscopy can be used as a tool for interrogating electrons in resist and electrons owing from underlayers to resists. The electron energy distribution, albeit different from that measured with condensed phase photoemission spectroscopy, can be recovered computationally. The computational approach involves Monte Carlo simulations using the energy resolved scattering mean free path and the photoemission energy spectra as inputs.