IMPACT OF THE PURITY OF SILICON ON THE EVOLUTION OF ION BEAM GENERATED DEFECTS: FROM RESEARCH TO TECHNOLOGY

摘要

The experiments illustrated in this article indicate that the point defects generated by ion beam are mobile at room temperature in silicon. However, their migration is dramatically affected by the purity of silicon, due to trapping of point defects at impurities or defects. These phenomena can be exploited to suppress the transient enhanced diffusion of boron, in order to obtain shallow junctions necessary for the modern semiconductor devices. The purity of silicon has a severe impact also on the electrical activation of such doped layers. The implanted dopant, in fact, forms complexes with the impurities present in the substrate loosing its electrical activity.