Nowadays, microelectronic devices are omnipresent in our everyday life. To make them smaller and smaller as well as smarter and smarter, a new process which consists in stacking integrated circuits is being studied. In order to build this type of structures, the fabrication of microvias between layers is key. This work ultimately aims at developing an innovative process with reduced cost for the efficient metallization of these microvias. This can be achieved using perfectly calibrated metallic nanoparticles (NPs). In particular, bimetallic Mn-CuNPs could be interesting precursors to grow “self-formed” barriers and seed layers in microvias. Ionic liquids (ILs) are extremely well adapted media for the synthesis of such nano-objects, especially when organometallic precursors are used. It has been shown that theirspecific 3D structure provides a template to grow RuNPs of controlled size. The IL also acts as stabilizer, eliminating the need to use ligands that contaminate the metallic surface. In this work, this concept have been extended to the synthesis of other metallic NPs, such as Cu and Mn, as well as synthesis of NPs containing the two metals (bimetallic M-M’NPs). Remarkably, these M-M’NPs always exhibit a smaller size than the MNPs and M’NPs separately. These homogeneous and stable suspensions have been directly applied and sintered onto technological substrates in order to form uniform and adherent metallic layers.
