Enhancement of the Thermal Stability of TiN(x) Capping Layer on the Nickel Silicides

Abstract

In this study, the effects of TiN(x) capping layers on the thermal stability of nickel silicides have been investigated in a rapid thermal annealing (RTA) process. Various TiN(x) films were deposited on the nickel film by different N(2) flow rates. It was found that the TIN(x) capping layer could improve the thermal stability of nickel silicides and suppress silicide agglomeration. The TIN(x) 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 TIN(x) films deposited with various N(2) flow rates and nickel films in the H(2)SO(4):H(2)O(2) (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 TiN(x) films, while the I(corr) of the TiN(x) films deposited with higher N(2) flow rates was much lower than that of the TiN(x) films deposited with lower N(2) flow rates.