Aspects of TiN and Ti deposition in an ECR plasma enhanced CVD process

Tetrakis(dimethylamido) titanium (TDMAT) was used to deposit pure TiN at temperatures < 300°C by introducing it into the downstream region of an electron cyclotron resonance (ECR) plasma using nitrogen as plasma gas. The mechanism of TiN formation from TDMAT was elucidated with labeled nitrogen as plasma gas. Titanium was deposited on silicon at 500°C using titanium tetrachloride (TiCl4) and a hydrogen ECR downstream plasma. The formation of titanium disilicide was confirmed by X-ray photoelectron spectroscopy (XPS) after annealing the Ti film on silicon at 800°C. After silicide formation, a TiN cap was deposited from TiCl4 and a nitrogen/hydrogen plasma gas mixture. The chlorine content of the film was less than 1 at%. Thus, the combination of the TiCl4 and TDMAT process is a possible approach for contact level and upper level metallization.