Excimer-laser activation of dopants in silicon: a new concept for a uniform treatment over a whole die area

Formation of ultra shallow junction will need laser annealing process in an imminent future. The VEL 15 laser source from SOPRA allows to anneal in a single shot a complete die with /spl plusmn/3.5% uniformity, and with enough energy to melt silicon and activate dopants. Boron and BF/sub 2/ implanted wafers have been laser annealed, and then characterized with different techniques. Ultra shallow junction around 20 nm and less than 400 Ohms/sq have been performed. Feasibility of highly activated p-type junction is demonstrated with a whole die area exposition.