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Two new precursors for focused electron beam-induced deposition (FEBID) of cobalt silicides have been synthesized and evaluated. The H3SiCo(CO)4 and H2Si(Co(CO)4)2 single-source precursors retain the initial metal ratios and show low sensitivity to changes in the FEBID parameters such as acceleration voltage, beam current, and precursor pressure. The precursors allow the direct writing of material containing ∼55 to 60 at % total metal/metalloid content combined with high growth rates. During the deposition process an average of ∼80% of the carbonyl ligands are cleaved off in these planar deposits. Postgrowth electron curing does not change the deposits' composition, but resistivities decrease after the curing procedure. Temperature-dependent electrical properties indicate the presence of a granular metal for both cured samples and the as-grown Co2Si deposit, while the as-grown CoSi material is on the insulating side of the metal-insulator transition. The observed magnetoresistance behavior is indicative of tunneling magnetoresistance and is substantially reduced upon postgrowth irradiation treatment.

Focused electron beam-induced deposition (FEBID) is a maskless, direct-write nanolithography approach for the growth of nanostructures. In recent years, significant progress has been made demonstrating highly controlled writing processes with complex nanostructure geometries and intricate methods of preparing inorganic deposits of sufficient purity for applications in materials science and condensed matter physics. For instance, fields of research include sensors, electrical contacts, magnetics, photonics etc. The deposition process itself is simple and highly complex at the same time. Interdisciplinary efforts are required to understand individual reaction paths in the molecule–electron interactions and the impact of several parameters governing the overall process that determines the material's composition. Since the deposition hinges on volatile precursors, a description of chemical aspects and potential avenues for the development of tailored precursor synthesis are described herein. Literature data are used to describe the process and the influence of the precursor constitution on the deposits’ nature. Results on molecule–electron interactions in the gas phase as well as condensed precursor layers are compared to FEBID deposit's composition illustrating the benefits and shortcomings of these supporting investigations in explaining the precursor decomposition characteristics in FEBID processes. This is also associated with the need of understanding the role of deposition conditions and reporting as many details as possible in experimental sections, which is of utmost importance in order to ensure reproducibility of reported data in the FEBID community. Moreover, we outline the potential impact of the vacuum level and associated water content in the deposition equipment on the deposited material's composition, which should be a major contributor to the compositional variations being described in the literature. A few additional experiments are suggested to unravel the impact of this parameter enabling secondary reaction paths in the FEBID process initiated by water–molecule–electron interactions. Finally, we summarize the classes of precursors used for FEBID to date and add our thoughts on approaches how to choose new precursors for this direct-write technique.

Thioether-functionalised indium aminoalcoholates have been used as single-source precursors in aerosol-assisted CVD processes. The obtained In2O3−xSx oxysulphide deposits show either a single indium sulphide phase for deposits with high sulphide content [>75% (S/(S + O)) for the t-butyl derivatives] or pronounced phase separation in indium oxide and indium sulphide for lower sulphide content [