Tantalum nitride films deposited at various substrate temperatures onto Si(001) substrates could produce amorphous and crystalline phase with different preferred orientations. Subsequently, the viability of employing them as the diffusion barriers between Cu and Si was investigated by annealing at various temperatures for 0.5h. The characterization of the thin films was carried out by 4-point probe and X-ray diffraction. The results indicated that the thermal stability of Ta2N with Cu and Si were dependent on the crystallinity of Ta2N. Ta2N phase with the highest (002) preferred orientation exhibits the highest structural stability to prevent Cu diffusion more effectively.

Effect of Crystallinity and Preferred Orientation of Ta2N Films on Diffusion Barrier Properties for Copper Metallization. H.C.Chung, C.P.Liu: Surface and Coatings Technology, 2006, 200[10], 3122-6