Synthesis of new classes of FEBID precursors

Several novel precursors have been synthesized and their performance in the FEBID process has been evaluated.

Novel bimetallic precursors

The novel precursor HFeCo₃(CO)₁₂ was synthesized and and yields FeCo₃ metallic phases with predefined stochiometry and metal content up to 80% in the FEBID process:

• F. Porrati, M. Pohlit, J. Müller, S. Barth, F. Biegger, C. Gspan, H. Plank, M. Huth:
  Direct writing of CoFe alloy nanostructures by focused electron beam induced deposition from a heteronuclear precursor,
  Nanotechnology 26 (2015) 475701.

Novel Ru precursor (η³-C₃H₅)Ru(CO)₃Br

CO ligands readily detaches from this precursor and Br can be removed by applying larger electron exposures. However, despite the fact that loss of the allyl ligand is also an important process observed in the gas phase, carbon remains behind upon decomposition on a surface:

• Rachel M. Thorman, Joseph A. Brannaka, Lisa McElwee-White, Oddur Ingolfsson:
  Low energy electron-induced decomposition of (η³-C₃H₅)Ru(CO)₃Br, a potential focused electron beam induced deposition precursor with a heteroleptic ligand set,
  Phys.Chem.Chem.Phys. 19 (2017) 13264-13271.

• Julie A. Spencer, Joseph A. Brannaka, Michael Barclay, Lisa McElwee-White,
  D. Howard Fairbrother:
  Electron-Induced Surface Reactions of η³‑Allyl Ruthenium Tricarbonyl Bromide [(η³‑C₃H₅)Ru(CO)₃Br]: Contrasting the Behavior of Different Ligands
  J. Phys. Chem. C 119 (2015) 15349−15359.

Silacyclohexane precusors

Novel silacyclohexane precursors are favourable for deposition of silicon carbides as they retain the initial stochiometry in the deposit:

• Ragesh Kumar T P, Sangeetha Hari, Krishna K Damodaran, Oddur Ingólfsson, Cornelis W. Hagen:
  Electron beam induced deposition of silacyclohexane and dichlorosilacyclohexane: the role of dissociative ionization and dissociative electron attachment in the deposition process,
  Beilstein J. Nanotechnol. 8 (2017) 2376–2388.

Small volatile Au precursors

Evaluation in the FEBID process has revealed that [ClAu(III)Me₂]₂ and MeAu(I)(PMe₃) are suitable precursors for Au deposition:

• W. F. van Dorp, X. Wu, J. J. L. Mulders, S. Harder, P. Rudolf, J. T. M. De Hosson,
  Gold Complexes for Focused-Electron-Beam-Induced Deposition
  Langmuir 2014, 30, 12097−12105.

Novel precursor for deposition of high-purity Ag

In the FEBID process, Ag-(2,2-dimethylbutanoato-κO) yields Ag deposits with purities up to 75%:

• Katja Höflich, Jakub Jurczyk, Yucheng Zhang, Marcos V. Puydinger dos Santos, Maximilian Götz, Carlos Guerra-Nuñez, James P. Best, Czeslaw Kapusta, Ivo Utke:
  Direct Electron Beam Writing of Silver-Based Nanostructures,
  ACS Appl. Mater. Interfaces, 9 (2017) 24071–24077.