Formation of TiN films with low Cl concentration by pulsed plasma chemical vapor deposition

Polycrystalline TiN films containing less than 1 at. % of Cl contamination were formed from TiCl4 at a low temperature (200 degrees C) condition on a Si substrate by pulsed plasma chemical vapor deposition. The Cl suppression at low temperature was realized by a two-step process, TiCl4 decomposition and hydrogen reduction. The main objective for reducing Cl in the film was to establish a sufficient reduction period to free TiClx radicals in the gas phase. The length of the reduction period was affected by the radio frequency power, which decided the rate of TiCl4 decomposition and hydrogen reduction. (C) 1996 American Vacuum Society.