On the balance between ion beam induced nanoparticle formation and displacive precipitate resolution in the C-Si system

Nano-crystals of 3C-SiC can be formed in crystalline silicon with an almost monomodal size distribution by implanting high doses of carbon ions into silicon. The narrow size distribution is thought to be due to a balance between beam-induced precipitate formation and destruction mechanisms. To study the effect of high diffusivities on this balance, in the present investigation carbon implantations were performed at temperatures of 700-1000 °C and studied by ERDA, RBS, HRXRD, TEM and STEM. It is found that strained dendritic nano-crystals form at a growth rate apparently governed by the diffusion of C-SiI complexes to the growing precipitates. The observations allow us to conclude general rules for identifying materials systems in which monomodal precipitate distributions may be expected.