The self-diffusion of silicon in magnetron-sputtered silicon carbide films deposited onto different substrates (crystalline silicon, glassy carbon) was investigated. Because the crystallization of amorphous silicon carbide films depended strongly upon the substrate, the diffusivity of silicon was also expected to depend upon the substrate. Isotope hetero-structures and secondary ion mass spectrometry were used. For amorphous samples, an upper limit on the diffusivity of 10−21m2/s was deduced at 1100C. For crystallized films, diffusivities at between 1350 and 1600C were not significantly different for the two types of substrate. For samples deposited onto glassy carbon substrates, an activation enthalpy of 8.7eV was found for the self-diffusion of Si.

Si Diffusion in Magnetron Sputtered Silicon Carbide Films Deposited on Silicon and Carbon Substrates. W.Gruber, U.Geckle, M.Bruns, H.Schmidt: Thin Solid Films, 2009, 518[1], 396-8