Detection of surface accumulation of dopants in rapid-thermally-annealed, shallow-implant silicon

Rapid thermal annealing (RTA) of ion-implanted silicon is a procedure for annealing the damage caused by implantation while minimizing the redistribution of the implanted dopant species. The accumulation of dopant atoms at interfaces and at the surface as a result of the annealing can have significant effects on the electrical properties of the material. We have studied the surface accumulation of B and Sb implanted at low energy into silicon (with a subsequent RTA cycle) by using low-energy ion scattering, nuclear reaction analysis, and Rutherford backscattering. The use of these complementary techniques has enabled the confirmation of the presence of surface accumulation of dopant material in each case. Each technique leads to different specific information.