The implantation of B ions into pre-amorphized material was studied. The pre-amorphization was achieved by F+ or Si+ implantation before 10keV B+ implantation to a dose of 3 x 1015/cm2. Broadening of the B profile could be markedly suppressed in the pre-amorphized layers. The as-implanted depth at a B concentration of 1018/cm3 decreased from 0.19 to 0.1μm for implantation into a pre-amorphized layer, as compared to B implantation into crystalline Si. During annealing at 950C, the B atoms diffused much more rapidly in the pre-amorphized layers than in the crystalline material. During dual F+ and B+ implantation, using F+ doses above 1015/cm2, the F was found to segregate to the peak of the B profile during annealing. The F was also trapped at the peak of the as-implanted F profile peak and near to the amorphous/crystalline interface.

Diffusion of Ion-Implanted Boron Impurities into Pre-Amorphized Silicon. N.Ohno, T.Hara, Y.Matsunaga, M.I.Current, F.Inoue: Materials Science in Semiconductor Processing, 2000, 3[3], 221-5