FORMATION MECHANISM OF TIN BY REACTION OF TETRAKIS(DIMETHYLAMIDO)-TITANIUM WITH PLASMA-ACTIVATED NITROGEN

The metallorganic tetrakis(dimethylamido)-titanium [Ti(NMe(2))(4)] reacts with electron cyclotron resonance plasma-activated nitrogen in the downstream region to form low resistivity crystalline TiN films at substrate temperatures as low as 100 degrees C. The ability to deposit this refractory material at such low temperatures is indicative of a nonthermally activated process. Experiments with labeled nitrogen show that the nitrogen in the TiN films is derived almost exclusively from the plasma gas. Chemical ionization mass spectrometry investigations of the gas mixture in the reactor using labeled nitrogen as the plasma gas reveal the formation of unlabeled amines and what we assign to be a three-membered metallacycle intermediate. The results show that the dimethylamido groups are substituted by plasma-activated nitrogen to form pure TiN films. For the first time an almost complete substitution of the ligands on a metallorganic compound using plasma-activated species has been demonstrated.