The effect of preamorphization using silicon (Si) ion, different annealing temperatures and heating rates on nucleation density and grain size of C49 and C54–TiSi2 have been studied. The average grain size of C54–TiSi2 is found to decrease when the peak annealing temperature is changed from 700 to 850 °C. We found that the nucleation threshold temperature is about 900 °C at which the C54–TiSi2 grain size levels off at about 23 nm. We also found that the grain size of C54–TiSi2 is independent of different heating rates. Our results also show that preamorphization is not so effective in reducing the C54–TiSi2 grains when annealing temperature is raised to above 850 °C. However, preamorphization does improve the grain size uniformity. By optimizing the processing parameters such as peak annealing temperature, heating rates and preamorphization, we have demonstrated the formation of C54–TiSi2 on 0.12 μm polycrystalline silicon (polysilicon) lines with no agglomeration. © 2003 American Institute of Physics.