In this study, the physical and electrical properties as well as thermal stability of sputter-deposited titanium carbide (TiCa) films as diffusion harriers for Cu metallization were investigated for the first time. With thermal annealing in N2 ambient for 30 min, the unpatterned Cu (2000 Å)/TiCA (500 Å)/n-Si structure was found to be metallurgically stable up to a temperature between 600 and 650°C without formation of a Cu3Si phase, while the reverse leakage current of the patterned Cu (2000 Å)/TiC, (500 Å)/p n-Si diode structures showed that the TiC, harrier layer was capable of withstanding annealing temperatures up to 500°C. The failure of the TiCx layer after high temperature annealing is attributed to the diffusion of Cu along localized defects or grain boundaries of the TiCx barrier layer into Si substrate, which caused the high junction leakage currents for the patterned structure and formation of Cu3Si for the unpallerned structure.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry