Electrical characterization of platinum and palladium effects in nickel monosilicide/n-Si Schottky contacts

The current versus voltage (I-V) characteristics of Ni(Pt or Pd)Si/n-Si Schottky contacts annealed at 400 and 500 °C showed that the Schottky barrier height (SBH) of the contact increased from 0.67 to 0.80 eV with an addition of 10 at.% Pt into the Ni alloy film. On the other hand, both 5 and 10 at.% Pd resulted in the same amount of increase in the SBH. The forward-biased I-V characteristics of Ni alloy/Si contacts carried out at 93 to 300 K showed that at higher measured temperature (> 253 K), or at low measured temperature (< 253 K) but at higher bias (> 0.5 V), it can be modeled using the thermionic emission model with the SBH decreased and ideality factor increased with decreasing temperature. Excess current was observed when measured at T < 253 K and lower bias (< 0.5 V) which may be due to the local inhomogeneity of SBH.