The phase sequence of the rapid thermal processing induced reaction at T=650 °C has been studied by a combination of high resolution transmission electron microscopy and image simulations. We found that pre-amorphization of poly-Si substrates does not change the reaction path, i.e., Ti5Si4 and C-49 TiSi2 phases were formed with the latter growing upon further annealing. In the Mo doped poly-Si/Ti system the C-54 TiSi2 phase forms along with Ti5Si4 and two Mo silicide phases, MoSi2 and Mo5Si3; no C-49 TiSi2 was observed. We provide direct evidence that the Ti–Si reaction in the Mo doped system follows the template mechanism with MoSi2 and Mo5Si3 based phases acting as template phases for accelerated growth of C-54 TiSi2. Direct formation of C-54 TiSi2 at lower temperatures bypassing C-49 TiSi2 is very promising for application of the Ti salicide process in the future generation of deep-submicron complementary metal–oxide–semiconductor devices.