Precise Ion Implantation for Advanced MOS LSIs

摘要

Issues in the ion implantation technology employed in advanced MOSLSIs are addressed, where the placement of implanted impurities will directly influence the device performance and yield. The importance of precise control of the incident angle of ion beam is discussed; the poor precision results in the deviation of V_(th) and I_(dsat) and asymmetry of them. Next, the effect of energy contamination caused by the deceleration of ions in front of a substrate (in order to obtain high beam current at low energy) on device characteristics is presented. Provisions in ion implanters for these issues are referred briefly. Defect generation during implantation and the impacts of the defects on the advanced device characteristics are also addressed. It is demonstrated that the amount of point defects is influenced by the implantation conditions and method, and the amount influences the redistribution of implanted impurities and activation during annealing.