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arXiv · 0811.0806

The mechanism of ion induced amorphization in Si

H. P. Lenka·U. M. Bhatta·P. K. Kuiri·G. Sahu·B. Joseph·B. Satpati·D. P. Mahapatra
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Abstract

Some results on damage build up in, and amorphization of, Si, induced by 25-30 keV Al$_5^-$, Si$_5^-$ 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 $\sim 1.6$, 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.

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H. P. Lenka, U. M. Bhatta, P. K. Kuiri, G. Sahu, B. Joseph, B. Satpati, D. P. Mahapatra. 2009-02-16. The mechanism of ion induced amorphization in Si. https://arxiv.org/abs/0811.0806

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