Electron Induced Surface Reactions of HFeCo3(CO)12, a Bimetallic Precursor for Focused Electron Beam Induced Deposition (FEBID)

Abstract

The use of bimetallic precursors in focused electron beam induced deposition (FEBID) allows mixed metal nanostructures with well-defined metal ratios to be generated in a single step process. HFeCo3(CO)12 is an example of one such bimetallic precursor that has previously been shown to form deposits with unusually high metal content (>80%) as compared to that of typical FEBID deposits (<30% metal content). To better understand the elementary bond breaking steps involved in FEBID of HFeCo3(CO)12, we have employed a UHV surface science approach to study the effect of electron irradiation on nanometer thick films of HFeCo3(CO)12 molecules. Using a combination of in situ X-ray photoelectron spectroscopy and mass spectrometry, we observed that the initial step of electron induced HFeCo3(CO)12 dissociation is accompanied by desorption of ∼75% of the CO ligands from the precursor. A comparison with recent gas phase studies of HFeCo3(CO)12 indicates that this process is consistent with a dissociative ionization pr...