Titanium monophosphide (TiP) layers as potential diffusion barriers

Summary form only given. Usually, diffusion barrier layers are fabricated of titanium nitride, deposited either by sputtering or by CVD. We developed a rapid thermal-CVD process with the classical precursor combination TiCl4/NH3 for temperatures <or=450 degrees C. The chlorine content still present in the as-deposited coatings is reduced below a critical threshold of 2 at% by a subsequent in-situ annealing step in NH3. Such barrier layers were successfully applied in test circuits.