Characteristics of TiN thin films grown by ALD using TiCl4and NH3

Titanium nitride thin film was deposited on a silicon wafer by the Atomic Layer Deposition (ALD) method using TiCl4 and NH3 as source chemicals. Nitrogen gas was used for carrying the TiCl4 and purging the reactants. The gases were introduced into the reaction chamber in the sequence of TiCl4-N-2-NH3-N-2 for the saturated surface reaction on the wafer. TiN film was grown with [100] preferred orientation at 350degreesC, while with [111] preferred orientation at 450degreesC and higher temperatures. The deposition rate was constant as 0.17 Angstrom/cycle irrespective of deposition temperature, which demonstrates TiN film was grown by the ALD growth mechanism. TiN thin films grown at a temperature higher than 450degreesC with thickness of 320 Angstrom showed electrical resistivity as low as 72x10(-6) Omegacm.