In this paper we study the influence of post-growth wafer cutting of hetero-epitaxial 3C-SiC on Si substrate for 6 and 8 inches wafers. We find an increase of wafer curvature after each cut process and a correspondent variation of the Raman shift. This result, confirmed by FEM, can be explained in term of the wafer symmetry breaking and the related relaxation under modified constrains due to the cutting. The FEM analysis of the deformation state reveals a modification of the residual stress tensor which changes from a pure biaxial form to a more complicated one containing diagonal and off-diagonal components.