Damage control with cluster ion implantation

Ion implantation is doping process for manufacturing semiconductor. Doping process contains not only implanting doping atoms at a controlled depth profile but also making damages caused by collisions between ions and silicon crystal atoms, knock-on silicon atoms and silicon crystal atoms. A characteristic of doping atoms such as boron, phosphorous and arsenic is well known because it is easy to measure its resistivity and depth profile. On the other hand it is difficult to measure damages. The damage consist vacancies and interstitials in silicon crystals. We have to measure nothing and same atoms in the same crystal atoms. In order to measure damages characteristics we have to fabricate transistor devices, because damages region after thermal budget is too small to measure.