Ecr Plasma Enhanced MOCVD of Titanium Nitride

The ability to deposit high purity TiN by a CVD process that can provide improved conformality over current sputter deposition processes is critical for multilevel Si ULSI device applications. Low temperature deposition of high quality TiN films has been achieved by an ECR plasma enhanced CVD process using the metal-organic precursor, tetrakis(dimethylamido) titanium, Ti(N(CH 3 ) 2 ) 4 (TDMAT). TDMAT is introduced into the downstream region of either a N 2 or NH 3 ECR plasma to deposit highly conducting films at deposition temperatures of as low as 100°C. The electrical resistivity of the TiN films decreases from 100-150μΩ-cm at a deposition temperature of 100°C to 45μΩ-cm at 600°C. The choice of plasma gas, N 2 or NH 3 , affects the composition as well as the crystallographic texture of the films, which exhibit preferred (200) and (111) orientations, respectively. Pretreatment of the Si substrate with N 2 or NH 3 plasmas also affects the film morphologies, as demonstrated by switching the plasma gas between pretreatment and deposition.