Site-Selective Chemical Vapor Deposition on Direct-Write 3D Nanoarchitectures

Recent advancements in additive manufacturing have enabled the preparation of free-shaped 3D objects with feature sizes down to and below the micrometer scale. Among the fabrication methods, focused electron beam-and focused ion beam-induced deposition (FEBID and FIBID, respectively) associate high flexibility and unmatched accuracy in 3D writing with a wide material portfolio, thereby allowing for the growth of metallic to insulating materials. The combination of the free-shaped 3D nanowriting with established chemical vapor deposition (CVD) techniques provides attractive opportunities to synthesize complex 3D core-shell heterostructures. Hence, this hybrid approach enables the fabrication of morphologically tunable layer-based nanostructures with the great potential of unlocking further functionalities. Here, the fundamentals of such a hybrid approach are demonstrated by preparing core-shell heterostructures using 3D FEBID scaffolds for site-selective CVD. In particular, 3D microbridges are printed by FEBID with the (CH3)3CH3C5H4Pt precursor and coated by thermal CVD using the Nb(NMe2)3(N-t-Bu) and HFeCo3(CO)12 precursors. Two model systems on the basis of CVD layers consisting of a superconducting NbC-based layer and a ferromagnetic Co3Fe layer are prepared and characterized with regard to their composition, microstructure, and magneto-transport properties.