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arXiv · 0805.0066

Study of low energy Si$_5^-$ and Cs$^-$ implantation induced amorphization effects in Si(100)

H. P. Lenka·B. Joseph·P. K. Kuiri·G. Sahu·P. Mishra·D. Ghose·D. P. Mahapatra
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Abstract

The damage growth and surface modifications in Si(100), induced by 25 keV Si$_5^-$ cluster ions, as a function of fluence, $ϕ$, has been studied using atomic force microscopy (AFM) and channeling Rutherford backscattering spectrometry (CRBS). CRBS results indicate a nonlinear growth in damage from which it has been possible to get a threshold fluence, $ϕ_0$, for amorphization as $2.5\times 10^{13}$ ions-cm$^{-2}$. For $ϕ$ below $ϕ_0$, a growth in damage as well as surface roughness has been observed. At a $ϕ$ of $1\times 10^{14}$ ions-cm$^{-2}$, damage saturation coupled with a much reduced surface roughness has been found. In this case a power spectrum analysis of AFM data showed a significant drop, in spectral density, as compared to the same obtained for a fluence, $ϕ< ϕ_0$. This drop, together with damage saturation, can be correlated with a transition to a stress relaxed amorphous phase. Irradiation with similar mass Cs$^-$ ions, at the same energy and fluence, has been found to result in a reduced accumulation of defects in the near surface region leading to reduced surface features.

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H. P. Lenka, B. Joseph, P. K. Kuiri, G. Sahu, P. Mishra, D. Ghose, D. P. Mahapatra. 2008-06-04. Study of low energy Si$_5^-$ and Cs$^-$ implantation induced amorphization effects in Si(100). https://doi.org/10.1088/0022-3727/41/21/215305

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