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We present results on chloride-based homoepitaxial growth of SiC in a hot wall CVD reactor. The addition of chlorinated species to the gas mixture prevents silicon nucleation in the gas-phase, thus allowing higher input flows of the precursors to grow epitaxial layers with very high growth rate. We have achieved growth rates of more than 100µm/h, as compared to 5µm/h for the standard SiC epitaxial growth using SiH4, and C2H4, as precursors. The chlorinated precursor used is methyltrichlorosilane (MTS), Cl3SiCH3, but since MTS contains both silicon and carbon, with the C/Si ratio 1, we have also added silane and ethylene to optimise the C/Si ratio in order to improve the morphology of the epitaxial layers. We present studies of how the growth rate depends on both the flow of MTS and the growth temperature. The morphology of the grown epitaxial layer has been investigated using Nomarski microscope and atomic force microscope showing extremely smooth surface and low epi-defect density. The doping level has been determined using capacitance-voltage measurements. The residual doping is less than 1·1014 cm-3. Low temperature photoluminescence and XRD measurements confirm the high quality of the grown epilayers. |