Ultra low energy (ULE) implant dose and activation monitoring

This paper describes newly developed techniques to accurately measure the 4pp sheet resistance without the influences of probe penetration. Also, the electrically active surface dopant density (NSURF) is measured directly with a single non-penetrating, non-damaging and non-contaminating EM-probe. There are two types of EM-probes available; one for capacitance-voltage (CV) applications and the other for current-voltage (IV) applications. It was found that the EM-probe 4pp could measure source-drain extensions (SDE) structures and p/n ultra-shallow junction (USJ) structures. Conventional 4pp were found to be limited to about 30 to 40 nm and deeper. Variations in dose and sheet resistance reveal valuable information about the ion implantation and annealing processes which seems to be a powerful characterization tool.