The sheet resistance of TiSi2 films formed on patterned sub-half micron n+ polysilicon lines has been observed to be higher than the sheet resistance of unpatterned blanket TiSi2 films. We have investigated this phenomenon, and determined that the TiSi2 thickness is not a function of linewidth, and that the resistivity increase in narrow n+ lines is caused primarily by incomplete phase transformation to the low-resistivity C54 phase. We have determined a physical model for the kinetics of this phase transformation, based on an Arrhenius-type atomic re-arrangement process, and we have determined an activation energy (Ea) of phase transformation for different linewidths. We have observed that this Ea increases non-linearly as a function of decreasing linewidth, contrary to conventional belief. We have hypothesized that this increase is due to increasing dominance of edge-related phenomena such as contaminant segregation, strain etc. Finally, we have demonstrated that by supplying this Ea through a high temperature (825°C) anneal, even applied for a short time (15 s), low sheet resistances (<4 Ω/ü) can be obtained down to 0.35 μ m lines.