Pulsed proton-beam annealing of Ir and Ir_xV_100-x thin films on silicon

A pulsed proton beam was used to anneal Ir and Ir_xV _100-x thin films deposited on Si single crystals. Compound phases were produced by local melting of the metal-Si interface. Phase identification was carried out by x-ray diffraction; while component distribution was determined by Auger electron spectroscopy and Rutherford backscattering spectrometry. The morphology of the silicide layers was examined using transmission electron microscopy; and Schottky barrier heights were determined by current-voltage measurements. At intermediate deposited energy densities (∼0.5 J/cm²) a controlled interfacial reaction was observed. In the case of Ir/Si, amorphous IrSi as well as polycrystalline IrSi and Ir ₂Si₃ was detected in the reacted region. For the codeposited Ir_xV_100-x film, with x=80 and 50, the interfacial layer reacting with the Si substrate maintained the Ir: V ratio of the as-deposited film. This is in contrast to the case of furnace annealing where preferred accumulation of Ir is observed.