Properties of plasma-enhanced atomic layer deposited TiCx films as a diffusion barrier for Cu metallization

摘要: Abstract TiC x films were grown on thermally SiO 2 substrate by atomic layer deposition (ALD) using tetrakis–neopentyl–titanium [Ti(CH C(CH 3 ) 4, TiNp 4 , Np = neopentyl, CH ] and direct plasma of H as a reactant at the temperature ranging from 200 to 400 °C. A narrow ALD window 275 300 °C was shown growth rate 0.054 nm/cycle obtained. The ALD-TiC formed nanocrystalline structure with rock-salt phase that confirmed X-ray diffractometry transmission electronic microscopy (TEM) analysis. Its resistivity dependent microstructure features characterized grain size crystallinity well its density, which could be controlled varying temperature. Resistivity ~ 600 μΩ cm obtained where is in window, optimizing condition. In this study, performance very thin (6 nm) diffusion barrier for Cu interconnects evaluated. results showed (80 nm)/ALD-TiC (6 nm)/Si stable after annealing 600 °C 30 min. Cross-sectional view TEM analysis combined energy-dispersive spectroscopy revealed failed through into Si 650 °C without interfacial reactions between layers.