Velocity map imaging and cross sections of Fe(CO)5 for FEBIP applications

Abstract

The present paper intends to be a new study of a widely used precursor in nanostructure deposition and FEBID processes with focus on its fragmentation at collisions with low energy electrons. Newer developments in nanotechnology with applications to focused electron beam-induced deposition (FEBID) and extreme ultraviolet lithography (EUVL) based on irradiation-induced chemistry come with advances in the size of the nanostructures at the surface and their flexibility in creating highly complex 3D structures. The deformation in the main structures of the FEBID process characterized by elongation, reduction in diameter of the main structure and the deposition of additional thin layers around the structure, on the substrate, are results of the secondary electrons effect, colliding with energies lower than 20 eV. Fe(CO)5 is one of the most used compounds in FEBID processes as it has a high vaporization pressure and has been shown to provide high-purity deposits (over 90%). This paper combines experiment and simulations to study electron scattering from Fe(CO)5, using Quantemol-N simulations with mass spectroscopy techniques to present the fragmentation pathways and channel distributions for each of the resulting negative ions at low electron energies, while experimental data on dissociative electron attachment make use of the velocity-sliced map imaging (VMI) technique to determine the anions at the incident electron energies. The Quantemol-N simulation package as a standalone is used to study collision processes of low-energy electrons with Fe(CO)5 molecules including elastic, electronic excitation, and dissociative electron attachment (DEA) cross sections for a wide range of process in nuclear industry, medical research and quantum chemistry.Graphical abstract