Mj. Caturla et al., DISORDERING AND DEFECT PRODUCTION IN SILICON BY KEV ION IRRADIATION STUDIED BY MOLECULAR-DYNAMICS, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 106(1-4), 1995, pp. 1-8
We discuss the use of molecular dynamics simulation methods to study d
isordering and ion implantation in silicon. We discuss the simulation
methodology and introduce the interatomic potential employed, with a c
ritical discussion of its applicability. We show that in silicon the d
isplacement cascade results in a distinct primary state of damage domi
nated by large pockets of highly unrelaxed amorphous-like disordered s
ilicon. The amorphous volume produced for 5 keV Si on Si cascades cont
ains approximate to 1000 atoms, corresponding to an energy cost of app
roximately 10 eV/atom. Replacement collision sequences are found to be
very short in silicon and as a result, very few point defects appear
as a consequence of the displacement cascade. We show that upon anneal
ing of the damage microstructure at high temperature, the amorphous po
ckets recrystallize and result in the freezing-in in the lattice of va
cancies, SIAs and their clusters. We discuss the effect of the ion mas
s on defect production and amorphization, and present results on the t
emperature dependence of the damage as well on the stability of the da
mage clusters for boron and arsenic cascades.