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Boron-rich compounds, such as silicon borides (SiB4 and SiB6) are attractive materials for the applications of high-temperature thermoelectrics due to their chemical and physical stability and relatively good thermoelectric properties in high temperatures. Additionally, the silicon borides are of potential technological importance in semiconductor engineering. Nowadays, with the shrinking dimensions of semiconductor device the formation of ultra-shallow junction is a main concern. It closely related to behaviors of dopant diffusion into silicon, oxide, and silicide. In particular, low solid solubility of boron in silicon makes the formation of ultrashallow junction difficult. When the concentration of boron exceeds its solubility limit, precipitates of a silicon boride can appear within silicon. Thus, understanding the formation and stability of silicon boride precipitates is one of key issues in semiconductor processing. By the demands the growth of nanostructured silicon borides is highly needed. Motivated by these issues, we developed a simple approach for the growth of axially heterostructured nanowires by using open-tube chemical vapor transfer method; SiB4-core/SiO2-shell and SiB4-core/B2O3-shell. These model structures are useful for the investigation of boron diffusion behavior in silicon and oxide and can be directly applicable to practical applications, such as high-temperature thermoelectric devices and solid-state neutron detectors. |