+\section{Results}
+First versions of this simulation just covered the limited depth region of the target in which selforganisation is observed [13,14].
+As can be seen in Fig. 3, the new version of the simulation code is able to model the whole depth region affected by the irradiation process and properly describes the fluence dependence of the amorphous phase formation.
+In Fig 3a) only isolated amorphous cells exist in the simulation and cross-section transmission electron microscopy (XTEM) shows dark contrasts, corresponding to highly distorted regions caused by defects.
+XTEM at higher magnification [9] shows the existence of amorphous inclusions which are $3 \, nm$ in size.
+For a fluence of $2.1 \times 10^{17} cm^{-2}$ a continuous amorphous layer is formed (Fig. 3b)).
+The simulation shows a broader continuous layer than observed experimentally.
+However dark contrasts below the continuous layer in the XTEM image of Fig. 3b) indicate a high concentration of defects and amorphous inclusions in this depth zone.
+The continuous amorphous layer together with the region showing the dark contrast has essentially the same thickness as the simulated continuous layer.
+For higher fluences (Fig. 3c) and d)) experimental and simulated data correspond to a high degree.
+The thickness of the continuous amorphous layer increases with increasing fluence.
+Next to the upper crystalline/amorphous interface, nanometric lamellar inclusions are formed which get more defined with increasing fluence, reflecting the progress of selforganisation.
+The difference in depth throughought all images is due to a deeper maximum of the used {\em SRIM} implantation profile compared to older, more accurate {\em TRIM} versions.
+
+By simulation it is possible to determine the carbon concentration in crystalline and amorphous volumes.
+This is shown in Fig. 4.
+Lamellae exist between $350$ and $400 \, nm$ and cause a fluctuation in the carbon concentration.
+This is due to the carbon diffusion, which is of great importance for the ordering process, as already pointed out in [13,14], and the complementarily arranged and alternating sequence of layers with high and low amount of amorphous regions.
+In addition, a saturation limit of carbon in c-$Si$ under the given implantation conditions can be identified between $8$ and $10 \, at. \%$, the maxima of carbon concentration in crystalline volumes.
+
+Based on above results a recipe is proposed to create thick layers with lamellar structure which might be favourable for applications.
+The starting point is a crystalline silcon target with a nearly constant carbon concentration of $10 \, at.\%$ in a $500 \, nm$ thick surface layer. This can possibly be achieved by multiple energy ($180$ to $10 \, keV$) carbon implantation at a temperature of $500 \, ^{\circ} \mathrm{C}$, preventing amorphisation [5].
+In a second step the target is irradiated at $150 \, ^{\circ} \mathrm{C}$ with $2 \, MeV$ $C^+$ ions, which have a nearly constant energy loss in the top $500 \, nm$ and do not significantly change the carbon concentration here.
+The result is displayed in Fig. 5.
+Already ordered structures appear after $100 \times 10^6$ steps corresponding to a fluence of $D=2.7 \times 10^{17} cm^{-2}$ and get more defined with increasing fluence.
+According to recent studies [15] these structures are expected to be the starting point for materials showing strong photoluminescence.
+
+\section{Summary and conclusion}
+
+Ion irradiation of solids at certain implantation conditions may result in the formation of regularly ordered amorphous precipitates.
+The ordering process can be understood by the presented model, which is able to reproduce experimental observations by means of a Monte Carlo simulation code.
+Detailed information like the amount of carbon in amorphous and crystalline volumes is gained, shedding light on the selforganisation process.
+Finally a technique is proposed to produce thick films of ordered lamellar nanostructures.
+
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+\end{thebibliography}
+
+%\listoffigures
+
+\newpage
+\section*{Figure Captions}
+
+\begin{enumerate}
+\item Cross-sectional transmission electron microscopy (XTEM) image of a $Si(100)$ sample implanted with $180 \, keV$ $C^+$ ions at a fluence of $4.3 \times 10^{17} \, cm^{-2}$ and a substrate temperature of $150 \, ^{\circ} \mathrm{C}$. Lamellar and spherical amorphous inclusions at the interface of the continuous amorphous layer are marked by L and S.
+\item Schematic explaining the selforganised evolution of amorphous $SiC_x$ precipitates into ordered $SiC_x$ lamellae with increasing fluence (see text).
+\item Comparison of simulation and XTEM ($180 \, keV$ $C^+$ implantation into silicon at $150 \, ^{\circ} \mathrm{C}$) for several fluences. Amorphous cells are white. Simulation parameters: $p_b=0.01$, $p_c=0.001 \times (3\, nm)^3$, $p_s=0.0001 \times (3 \, nm)^5$, $d_r=0.05$, $d_v=1 \times 10^6$.
+\item Depth distribution of amorphous cells (white) (a) and corresponding carbon concentration profile for a fluence of $4.3 \times 10^{17} \, cm^{-2}$ (b) that shows separately the mean amount of carbon in amorphous and crystalline volumes as well as the sum of both.
+\item Prediction of the self-organised formation of amorphous nanolamellae upon $2 \, MeV$ $C^+$ irradiation of silicon homogeneously doped within the top $500 \, nm$ with $10 \, at. \%$ carbon. The fluence increases from (a) to (f) with $100 \times 10^6$ simulation steps corresponding to a fluence of $2.7 \times 10^{17} \, cm^{-2}$.
+\end{enumerate}
+
+\newpage
+\section*{Figures}
+
+\begin{figure}[!h]
+\begin{center}
+\includegraphics[width=14cm]{k393abild1_e.eps}
+\caption[1]{}
+\end{center}
+\label{img:tem}
+\end{figure}
+
+\newpage
+\begin{figure}[!h]
+\begin{center}
+\includegraphics[width=14cm]{modell_ng_e_nimb.eps}
+\caption[2]{}
+\end{center}
+\label{img:model}
+\end{figure}
+
+\newpage
+\begin{figure}[!h]
+\begin{center}
+\includegraphics[width=14cm]{dosis_entwicklung_all_e_2.eps}
+\caption[3]{}
+\end{center}
+\label{img:dose_cmp}
+\end{figure}
+
+\newpage
+\begin{figure}[!h]
+\begin{center}
+\includegraphics[width=14cm]{ac_cconc_ver3_e.eps}
+\caption[4]{}
+\end{center}
+\label{img:carbon_distr}
+\end{figure}
+
+\newpage
+\begin{figure}[!h]
+\begin{center}
+\includegraphics[width=14cm]{multiple_impl_e_2.eps}
+\caption[5]{}
+\end{center}
+\label{img:broad_lam}
+\end{figure}