In this paper, we present results obtained by Surface Enhanced Raman Scattering (SERS) on SWNTs films with different thicknesses. We show that the “D” band associated to disorder in graphitic compounds can also be due to intrinsic defects in SWNTs. In addition, we put in evidence strong interfacial reactions at the SWNTs/metallic support interface when NMP is used as solvent to disperse the tubes. Our observations suggest that these reactions can induce a breaking of the SWNTs. Presumably a reconstruction of compounds close to C60 molecules can occur.