Ultra-low energy ion implantation of boron for future silicon devices

Ion implantation has been a key process of microelectronics for the last 20 years. The production of ultra-shallow junctions, even shallower than 50 nm, which is necessary for future silicon devices, requires extreme performances from ion implantation and thermal processing. Ion beams with energies below 1 keV have been developed in order to challenge the severe specifications imposed by future device technologies. A new frontier of ion implantation has therefore been explored during the last few years and several novel aspects, specific to this energy regime, have been discovered. An overview on the main phenomena arising in silicon implanted with Boron at low and ultra-low energy is reported in this paper.