Fabrication and characterization of iridium silicide/silicon Schottky barrier

It is demonstrated that an IrSi/Si Schottky barrier can be formed by electron beam evaporation and annealing of Ir films on (100) Si at a temperature of around 450°C. Orientations of (100) and (002) in IrSi are preferred. The barrier height of IrSi/n-Si according to C-V measurements has been found to have a barrier height of 0.91 eV. Measurement of the absorptivity for IrSi indicates that thinner films benefit the infrared radiation absorption when the radiation approaches from the silicon side. An XPS study of IrSi/Si formation was performed. Chemical shift and variation of symmetry in the spectra of Ir, Si core level have been observed. The results suggest that chemical bonding and charge redistribution at the interface will contribute to the silicide Schottky barrier.