Thin films of TaBx interposed between Cu and Si were examined here as diffusion barriers for Cu metallization. In order to investigate the performance of Cu/TaBx/Si contact systems, X-ray diffraction, X-ray photoelectron spectroscopy, sheet resistance measurement, scanning electron microscopy, cross-sectional transmission electron microscopy and Auger electron spectroscopy depth profiling were used. Results of this study indicated that the barrier characteristics were significantly affected by the B/Ta ratio. In addition, the failure mechanism for the Cu/TaBx/Si contact systems was also discussed.

Characteristics of Sputtered TaBx Thin Films as Diffusion Barriers between Copper and Silicon. S.T.Lin, Y.L.Kuo, C.Lee: Applied Surface Science, 2003, 220[1-4], 349-58