Enhancement of the Thermal Stability of TiNx Capping Layer on the Nickel Silicides

Abstract

In this study, the effects of TiNx capping layers on the thermal stability of nickel silicides have been investigated in a rapid thermal annealing (RTA) process. Various TiNx films were deposited on the nickel film by different N-2 flow rates. It was found that the TINx capping layer could improve the thermal stability of nickel silicides and suppress silicide agglomeration. The TINx film deposited with higher N-2 flow rates had better thermal stability than those with lower N-2 flow rates. The corrosion behaviors of the TINx films deposited with various N-2 flow rates and nickel films in the H2SO4:H2O2 (4:1) solution were investigated. We found that the corrosion currents (I-corr) of the nickel and NiSi films were much higher than those of the TiNx films, while the I-corr of the TiNx films deposited with higher N-2 flow rates was much lower than that of the TiNx films deposited with lower N-2 flow rates.