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S. Barth, L. Hrachowina, F. Porrati, M. Hanefeld, P. Weirich, M. Huth, R. Kumar, R. Bjornsson, O. Ingolfsson:
"Synthesis of heteroleptic and -metallic precursors for focused electron beam induced deposition";
Talk: CELINA 2017 The fourth meeting of COST Action CM1301, Porto (invited); 2017-09-13 - 2017-09-16.

Homometallic carbonyls are widely used precursors for nanomaterial synthesis in gas phase processes and in liquids to form metallic coatings or nanostructures. Many of these carbonyls are commercially available and therefore they have been extensively studied. In particular, the deposition of metallic nanostructures by focused electron beam deposition (FEBID) using these homometallic carbonyls has been investigated and optimized in the recent past.[1, 2] In order to circumvent the use of multiple gas sources for the deposition of bimetallic nanostructures hetero-metallic carbonyls have been prepared.
As a proof of concept, HFeCo₃(CO)₁₂, DFeCo₃(CO)₁₂ and H₂FeRu₃(CO)₁₃ have been prepared and structurally compared.[3, 4] The heterometallic carbonyl clusters exhibit low vapor pressure; however, the compounds are volatile enough for the use in FEBID experiments. Despite the similarities in the cluster cores and also in the calculated energy levels, FEBID deposits differ significantly.

HFeCo₃(CO)₁₂ results in deposits with high metal content (> 80%) while the deposited material using H₂FeRu₃(CO)₁₃ contains significantly lower metal content. Structural and chemical similarities as well as differences can help to understand the decomposition behaviour of these molecular precursors.[5] In order to extend this approach of predefinition of deposit composition via precursor species, a compound containing metal and metalloid has been prepared. The Mn(CO)₅(SiH₃) precursor has been prepared by modified synthesis procedures but similar intermediates described in literature. In contrast to the termetallic precursors described vide supra, this precursor is highly volatilat room temperature due to low molecular mass and very limited intramolecular interactions. First results on deposit formation in the FEBIP process and deposit characterisation will be discussed.

http://publik.tuwien.ac.at/files/publik_263813.pdf