Synthesis and Characterization of Fe-C-Si System Ib-Type Gem-Grade Diamond Single Crystals under High Temperature and Pressure

This article presents a study of the phase composition and characteristics of slab diamond grown in the Fe-C-Si system at high temperature and pressure. The research investigates the influence of silicon on the growth of large-sized diamond single crystals and reveals that increasing the silicon content will roughen the diamond surface and significantly reduce the crystal growth rate. The study also found that silicon doping causes an increase in internal stress in the crystal and reduces diamond quality, as evidenced by a shift in the Raman peak and half peak width of the diamond. The nitrogen content was observed to reduce with the rise in silicon content, and the presence of nitrogen affects the impact of silicon doping into the crystal. The findings propose that there is an interaction between silicon and nitrogen during the synthesis process. This research provides insights into the potential applications of silicon-doped slab diamond crystals and highlights the importance of carefully controlling the silicon content to achieve the desired diamond quality.