Some results on damage build up in, and amorphization of, Si, induced by 25-30 keV Al5−, Si5− and Cs− ions, at room temperature, are reported. We show that at low energy, amorphization is a nucleation and growth process, based on the direct impact mechanism. With an Avrami exponent ∼1.6, the growth towards amorphization seems to be diffusion limited. A transition to a completely amorphized state is indicated at a dose exceeding 17 eV/atom, which is higher than 6-12 eV/atom as predicted by simulations. The observed higher threshold could be due to temperature effects although an underestimation of keV-energy recoils, in simulation, may not be ruled out.
@article{arxiv.0811.0806,
title = {The mechanism of ion induced amorphization in Si},
author = {H. P. Lenka and U. M. Bhatta and P. K. Kuiri and G. Sahu and B. Joseph and B. Satpati and D. P. Mahapatra},
journal= {arXiv preprint arXiv:0811.0806},
year = {2009}
}