Channeling on boron clusters in silicon

Low energy ion implantation at high doses of boron (> 10(15) cm(-2)) in Si is necessary for the fabrication of ultrashallow junctions but can result i n the undesirable presence of boron clusters. Values for the dimensions of the lattice distortions in the implanted Si are obtained by comparing the e nhanced dechanneling and the direct scattering peak in the region with clus ters in a channeled Rutherford backscattering spectrometry spectrum to thos e from Monte Carlo calculations on a curved crystal structure. Values of ab out 0.17 and 65 nm are found for the maximum deformation and the length of the distortions in the crystal, respectively, which implies that the lattic e distortions extend significantly outside the layer in which the B cluster s are supposed to be present. (C) 2001 American Institute of Physics.