Abstract
Using KrF excimer laser annealing with various laser pulse durations, we were able to form an ultra-shallow junction. Evaluating junction depth, sheet resistance, and crystal defects, we observed that in the case of long pulse durations, the number of crystal defects decreased. The combination of the junction depth and sheet resistance of the junction satisfied the request for a 90-nm node for ULSI. Furthermore, a MOSFET was fabricated by laser annealing with a heat assist. The heat assist is effective for reducing the required laser energy, crystal defects in the junction, and reducing laser damage to the electrode. We employed a simple onedimensional thermal diffusion model to estimate the solidification velocity during laser irradiation, with results indicating that longer pulse duration slowed the solidification velocity. Therefore, the behavior of the solidification velocity can explain the reduction of crystal defects.
