Characterization of elastic properties of hard carbon and boron nitride films using the Brillouin light scattering technique

The elastic properties of thin graphitic carbon and hexagonal boron nitride films have been determined by Brillouin light scattering from thermally ex cited surface acoustic phonons. The carbon films have been grown by plasma beam deposition at 420 degrees C. The BN films have been deposited by r.f.- magnetron sputtering and simultaneous ion plating. In the case of amorphous carbon a layered substructure has been found with a rather compliant inter mediate layer at the interface. The stiffness of the films increases with i ncreasing ion energy. As for carbon the BN coatings exhibit a pronounced el astic anisotropy indicating a preferred orientation of the hexagonal plants perpendicularly to the surface. The comparison of the Young's moduli deter mined by load indentation and by Brillouin light scattering allows the conc lusion that the material is composed of two or more components of different stiffness. (C) 2000 Elsevier Science S.A. All rights reserved.