The variation of the growth rate and step coverage at various padded HCl is presented in Figure . It can be noticed that the average growth rate drops nearly 50% when the padded HCl is increased to 5 Pa, which accounts for merely 0.5% of the total gas flow that is added to the process. A similar effect of HCl on the 3C-SiC growth in the MTS-H2 system was also reported by Lespiaux et. al., where the growth rate of 3C-SiC began to decrease at padded HCl/pMTS= 0.2 (in comparison to padded HCl/pSiCl4= 0.25 in the current study)