Velocity Map Imaging and Cross Sections of Fe(CO)5 for FEBIP Applications

TL;DR

This study combines experimental velocity map imaging and simulations to analyze low-energy electron collisions with Fe(CO)5, a key precursor in FEBID, revealing fragmentation pathways and cross sections relevant for nanostructure fabrication.

Contribution

It provides new experimental VMI data and detailed simulation results on electron scattering and dissociation channels of Fe(CO)5, enhancing understanding for FEBID applications.

Findings

Identified fragmentation pathways of Fe(CO)5 at low electron energies

Measured dissociative electron attachment cross sections

Mapped electron scattering processes relevant to nanostructure deposition

Abstract

The present paper intends to be a new study of a widely used precursor in nanostructure deposition and FEBID processes with a 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 effect of the secondary electrons, olliding with energies lower than 20eV. Fe(CO)5 is one of the most used compounds in FEBID processes as it has high 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, while experimental data on dissociative electron attachment is presented using the Velocity Slice Map Imaging (VMI) technique that combined with data collected on the CLUSTER apparatus at Comenius University, Bratislava and Quantemol-N simulations present the fragmentation pathways and channel distribution for each of the resulting negative ions at low energies. The Quantemol-N simulation package 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.