Integration of SALICIDE process for deep-submicron CMOS technology: effect of nitrogen/argon-amorphized implant on SALICIDE formation

We present a Ti–SALICIDE (self aligned silicide) process incorporating an argon or nitrogen-amorphization implantation prior to silicidation to enhance the C54-TiSi2 formation for deep submicron CMOS devices. It was found that by incorporating a high-temperature titanium deposition at 400°C together with amorphization, excellent sheet ρ was obtained for poly widths down to 0.25 μm. The improvement seen using a lower temperature (≈100°C) deposition was relatively less. We postulate that the higher-temperature deposition ensures that the C54 phase is nucleated before the C49 phase forms large grains. We also study the impact placed on maintaining the integrity of the active junctions and minimizing gate-to-source drain leakage. It was found that both argon and nitrogen result in anomalous leakage behavior, whereas arsenic was found to give excellent performance in terms of these parameters.