Cluster ion implantation for shallow junction formation

The implantation of Ar and B into Si by cluster ion has been examined. Shallow implantation was clearly demonstrated with a high energy cluster ion. The damage layer thickness is less than 200 /spl Aring/, when 150 keV Ar cluster ions are implanted into Si. This thickness is one order of magnitude smaller than that by Ar monomer ion bombardment with the same total energy. The thickness of the damaged layer formed by cluster ion bombardment increased with the cluster size, when the total energy of cluster ion remain the same. This is one of the non-linear effect of cluster implantation. Poly-atomic cluster-ion implantation with decaborane has also been demonstrated. Shallow implantation (<0.05 /spl mu/m) can be achieved by decaborane (B/sub 10/H/sub 14/) ions. The sheet resistance of the sample reached a few hundred /spl Omega///spl square/ after annealing at 1000/spl deg/C for 10 s.