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We have characterized 6H-SiC substrates with tip-enhanced Raman spectroscopy in a broad spectral range between 100 and 3000 cm^-1. A few adlayers of graphene previously grown on the semiconductor's C surface enabled us to approach the Au tip of a scanning tunneling microscope (STM) into tunnelling contact. In the recorded STM images of the substrate, we discern the height of the carbon adlayers in different sample regions. We compare tip-enhanced Raman (TER) spectra of the sample to normal Raman spectra recorded with the field vector of the linearly polarized light oriented at 30° or 90° with respect to the surface normal. All spectra show the phonon fingerprint of SiC and of graphene. We find the E1 modes of 6H-SiC selectively suppressed in the TER spectra whereas they are present in the normal Raman spectra excited at 30°. This effect is explained by a tip-induced symmetry change. © 2009 John Wiley & Sons, Ltd.