High-resolution transmission electron microscopy on silicon carbide whiskers

SiC whiskers were grown from the reaction of silicon monoxide (SiO) with activated carbon containing iron impurities. Growth proceeds through a VLS growth mechanism with SiO and CO as reacting gases. HRTEM combined with EDS shows that the SiC whisker is topped by a Fe₃Si catalyst droplet. The SiC whisker is found to be one-dimensionally disordered along the 111] growth direction of an fcc crystal structure. Although the catalyst droplet is usually larger than the top face of the whisker, we observed a number of situations where the diameter of the droplet was smaller. The study of the SiC-Fe₃Si interface showed that the growth is nucleated from the edges.