SiC single bulk crystals were grown using a high-temperature chemical vapor deposition (HTCVD) method, with SiH 4 and hydrocarbons as the source materials. SiH 4 is a pyrophoric gas, which frequently causes fatal accidents in experiments. In this study, therefore, we propose the use of a HTCVD method using tetramethylsilane (TMS), a cheap and safe precursor, for growing SiC bulk crystals. Although TMS contains C four times more than Si in its chemical formula, a stoichiometric SiC layer was successfully synthesized from TMS in the presence of a high concentration of H 2 based on the thermodynamic process design. 6H-SiC single crystals were successfully grown on a 6H-SiC seed crystal using the same process conditions. The resulting single crystalline layer was evaluated by rocking curve analysis by X-ray diffraction, which showed that the crystal properties of the grown SiC layer were improved compared to the seed crystals. This suggests that the TMS-based HTCVD method is feasible for practical use in SiC bulk growth.

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High temperature chemical vapor deposition (HTCVD), an alternate method for crystal growth of SiC, was recently deemed to be a safe method when tetramethylsilane (TMS) is used. In this study, we report on the characteristics of condensation of vapor species as a function of geometric location and temperature by analyzing outlet closing in TMS-based HTCVD under the conditions of 2000°C for 1-2 hours with a Si/H ratio of 6.2 × 10 −4 . Thermodynamic estimation of the classified reaction zones was experimentally verified by micro-Raman spectroscopy and microscopic inspections. 3148 | CrystEngComm, 2015, 17, 3148-3152 This journal isFig. 1 (a) Schematic of HTCVD reactor design used in this study. (b) Conceptual drawing of the reaction zones in the HTCVD reactor.

We introduce a one-step growth method for producing multilayer-graphene hollow nanospheres via a high-temperature chemical vapor deposition process using tetramethylsilane as an organic precursor. When the SiC nuclei were grown under an excess carbon atmosphere, they were surrounded via desorption of the hydrocarbon gas species, and graphene layers formed on the surface of the SiC nuclei via the rearrangement of solid carbon during the heating and cooling. The core SiC nuclei were spontaneously removed by the subsequent thermal decomposition, which also supplied the carbon for the graphene layers. Hence, multilayer-graphene hollow nanospheres were acquired via a one-step process, which was simply controlled by the growth temperature. In this growth process, the SiC nuclei acted as both the template and carbon source for the formation of multilayer-graphene hollow nanospheres.