The formation of CoSi 2 nanowires (NWs) via the annealing of Si NWs conformally coated with atomic layer deposited (ALD) Co layers was investigated. Co ALD was carried out using Co(iPr-AMD) 2 and NH 3 as a precursor and a reactant, respectively. Rapid thermal annealing (RTA) of CoSi core-shell NWs produced Co oxide instead of CoSi 2 due to oxygen contamination during annealing. To prevent oxygen contamination, a highly conformal ALD Ru layer was used as a capping layer. X-ray diffraction showed the formation of CoSi 2 when the Co/Si core-shell NWs were annealed at over 800°C. To investigate the deposition and silicidation process on a nanometer scale, high resolution C s-corrected scanning transmission electron microscopy was utilized with electron energy loss spectroscopy and energy dispersion spectroscopy. In contrast to previous reports on silicidation of NWs, the dominant diffusion species was found to be Si instead of Co based on a nucleation-controlled reaction.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry