To assess deformation issues in SiC/Si, different pre-growth procedures were investigated, involving the addition of SiH4 to C3H8 during the temperature ramps used for the carbonization. 3C-SiC layers were deposited on (001) and (111) Si substrates by VPE. The mechanical deformation of the wafer was measured by makyoh, obtaining 2D maps of the entire wafers. For the same pre-growth procedures, the substrate curvature depends strongly on the orientation of the substrate, (001) or (111), being generally lower for (111) substrates. The deformation results were compared with XRD and Raman spectroscopy. Plastic deformation of the substrate was evidenced by XRD, while the presence of tensile stress is suggested by Raman analysis.