\end{slide}
-% motivation
-
-\begin{slide}
-
-\headphd
- {\large\bf
- Polytypes of SiC\\[0.6cm]
- }
-
-\vspace{0.6cm}
-
-\includegraphics[width=3.8cm]{cubic_hex.eps}\\
-\begin{minipage}{1.9cm}
-{\tiny cubic (twist)}
-\end{minipage}
-\begin{minipage}{2.9cm}
-{\tiny hexagonal (no twist)}
-\end{minipage}
-
-\begin{picture}(0,0)(-150,0)
- \includegraphics[width=7cm]{polytypes.eps}
-\end{picture}
-
-\vspace{0.6cm}
-
-\footnotesize
-
-\begin{tabular}{l c c c c c c}
-\hline
- & 3C-SiC & 4H-SiC & 6H-SiC & Si & GaN & Diamond\\
-\hline
-Hardness [Mohs] & \multicolumn{3}{c}{------ 9.6 ------}& 6.5 & - & 10 \\
-Band gap [eV] & 2.36 & 3.23 & 3.03 & 1.12 & 3.39 & 5.5 \\
-Break down field [$10^6$ V/cm] & 4 & 3 & 3.2 & 0.6 & 5 & 10 \\
-Saturation drift velocity [$10^7$ cm/s] & 2.5 & 2.0 & 2.0 & 1 & 2.7 & 2.7 \\
-Electron mobility [cm$^2$/Vs] & 800 & 900 & 400 & 1100 & 900 & 2200 \\
-Hole mobility [cm$^2$/Vs] & 320 & 120 & 90 & 420 & 150 & 1600 \\
-Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\
-\hline
-\end{tabular}
-
-\begin{pspicture}(0,0)(0,0)
-\psellipse[linecolor=green](5.7,2.05)(0.4,0.50)
-\end{pspicture}
-\begin{pspicture}(0,0)(0,0)
-\psellipse[linecolor=green](5.6,0.89)(0.4,0.20)
-\end{pspicture}
-\begin{pspicture}(0,0)(0,0)
-\psellipse[linecolor=red](10.45,0.42)(0.4,0.20)
-\end{pspicture}
-
-\end{slide}
-
% fabrication
+\ifnum1=0
\begin{slide}
\headphd
\vspace{-0.5cm}
-\begin{center}
-\color{red}
-\framebox{
-{\footnotesize\color{black}
- Mismatch in \underline{thermal expansion coeefficient}
- and \underline{lattice parameter} w.r.t. substrate
-}
-}
-\end{center}
+%\begin{center}
+%\color{red}
+%\framebox{
+%{\footnotesize\color{black}
+% Mismatch in \underline{thermal expansion coeefficient}
+% and \underline{lattice parameter} w.r.t. substrate
+%}
+%}
+%\end{center}
\vspace{0.1cm}
\end{minipage}
}
\begin{minipage}{5.5cm}
-\begin{center}
-{\footnotesize
-No surface bending effects\\
-High areal homogenity\\[0.1cm]
-$\Downarrow$\\[0.1cm]
-Synthesis of large area SiC films possible
-}
-\end{center}
+ \includegraphics[width=5.8cm]{ibs_3c-sic.eps}\\[-0.2cm]
+ \begin{center}
+ {\tiny
+ XTEM: single crystalline 3C-SiC in Si\hkl(1 0 0)
+ }
+ \end{center}
\end{minipage}
+%\begin{minipage}{5.5cm}
+%\begin{center}
+%{\footnotesize
+%No surface bending effects\\
+%High areal homogenity\\[0.1cm]
+%$\Downarrow$\\[0.1cm]
+%Synthesis of large area SiC films possible
+%}
+%\end{center}
+%\end{minipage}
+
\end{slide}
+\fi
\begin{slide}
$\Rightarrow$ Epitaxial {\color{blue}3C-SiC} layer \&
{\color{blue}precipitates}
\item \underline{Implantation step 2}\\[0.1cm]
- Little remaining dose | \unit[180]{keV} | \degc{250}\\
+ Low remaining amount of dose | \unit[180]{keV} | \degc{250}\\
$\Rightarrow$
Destruction/Amorphization of precipitates at layer interface
\item \underline{Annealing}\\[0.1cm]
\end{slide}
-% contents
-
\begin{slide}
\headphd
\begin{itemize}
\item High-temperature implantation {\tiny\color{gray}/Nejim~et~al./}
\begin{itemize}
- \item C incorporated {\color{blue}substitutionally} on regular Si lattice sites
+ \item {\color{blue}Substitutionally} incorporated C on regular Si lattice sites
\item \si{} reacting with further C in cleared volume
\end{itemize}
\item Annealing behavior {\tiny\color{gray}/Serre~et~al./}
\end{itemize}
$\Rightarrow$ mobile {\color{red}\ci} opposed to
stable {\color{blue}\cs{}} configurations
-\item Strained silicon \& Si/SiC heterostructures
+\item Strained silicon \& Si$_{1-y}$C$_y$ heterostructures
{\tiny\color{gray}/Strane~et~al./Guedj~et~al./}
\begin{itemize}
- \item {\color{blue}Coherent} SiC precipitates (tensile strain)
+ \item Initial {\color{blue}coherent} SiC precipitates (tensile strain)
\item Incoherent SiC (strain relaxation)
\end{itemize}
\end{itemize}
\begin{slide}
+% contents
+
\headphd
{\large\bf
Outline
\scriptsize
-\vspace{0.1cm}
+\vspace{0.2cm}
\begin{minipage}{6.8cm}
\framebox{\hkl[0 0 -1] $\rightarrow$ \hkl[0 0 1]}\\
\end{minipage}
\begin{minipage}{5.4cm}
\includegraphics[width=6.0cm]{im_00-1_nosym_sp_fullct_thesis_vasp_s.ps}
-\end{minipage}\\[0.2cm]
+%\end{minipage}\\[0.2cm]
+\end{minipage}\\[0.3cm]
%\hrule
%
\begin{minipage}{6.8cm}
\includegraphics[width=6.0cm]{00-1_0-10_vasp_s.ps}
\end{minipage}\\[0.1cm]
%
-\begin{center}
-Reorientation pathway composed of two consecutive processes of the above type
-\end{center}
+%\begin{center}
+%Reorientation pathway composed of two consecutive processes of the above type
+%\end{center}
\end{slide}
\headphd
{\large\bf
- Summary / Conclusions
+ Summary and Conclusions
}
-\scriptsize
+\footnotesize
+
+\vspace{0.1cm}
\framebox{
\begin{minipage}{12.3cm}
\begin{itemize}
\item Point defects excellently / fairly well described
by DFT / EA
- \item C$_{\text{sub}}$ drastically underestimated by EA
- \item EA predicts correct ground state:
- C$_{\text{sub}}$ \& \si{} $>$ \ci{}
- \item Identified migration path explaining
- diffusion and reorientation experiments by DFT
- \item EA fails to describe \ci{} migration:
- Wrong path \& overestimated barrier
+ \item Identified \ci{} migration path
+ \item EA drastically overestimates the diffusion barrier
\end{itemize}
\item Combinations of defects
\begin{itemize}
\item Agglomeration of point defects energetically favorable
- by compensation of stress
- \item Formation of C-C unlikely
\item C$_{\text{sub}}$ favored conditions (conceivable in IBS)
\item \ci{} \hkl<1 0 0> $\leftrightarrow$ \cs{} \& \si{} \hkl<1 1 0>\\
Low barrier (\unit[0.77]{eV}) \& low capture radius
\begin{minipage}[t]{12.3cm}
\underline{Pecipitation simulations}
\begin{itemize}
- \item High C concentration $\rightarrow$ amorphous SiC like phase
\item Problem of potential enhanced slow phase space propagation
\item Low T $\rightarrow$ C-Si \hkl<1 0 0> dumbbell dominated structure
\item High T $\rightarrow$ C$_{\text{sub}}$ dominated structure
\item High T necessary to simulate IBS conditions (far from equilibrium)
- \item Precipitation by successive agglomeration of \cs (epitaxy)
+ \item Increased participation of \cs{} in the precipitation process
\item \si{}: vehicle to form \cs{} \& supply of Si \& stress compensation
(stretched SiC, interface)
\end{itemize}
}
\begin{center}
-{\color{blue}
+{\color{blue}\bf
\framebox{Precipitation by successive agglomeration of \cs{}}
}
\end{center}
\begin{slide}
- {\large\bf
- Acknowledgements
- }
+\headphd
+{\large\bf
+ Acknowledgements
+}
\vspace{0.1cm}
\underline{Augsburg}
\begin{itemize}
- \item Prof. B. Stritzker (accomodation at EP \RM{4})
- \item Ralf Utermann (EDV)
- \end{itemize}
-
- \underline{Berlin/Brandenburg}
- \begin{itemize}
- \item PD Volker Eyert (Ref)
+ \item Prof. B. Stritzker
+ \item Ralf Utermann
\end{itemize}
\underline{Helsinki}
\begin{itemize}
- \item Prof. K. Nordlund (MD)
+ \item Prof. K. Nordlund
\end{itemize}
\underline{Munich}
\begin{itemize}
- \item Bayerische Forschungsstiftung (financial support)
+ \item Bayerische Forschungsstiftung
\end{itemize}
\underline{Paderborn}
\begin{itemize}
- \item Prof. J. Lindner (SiC)
- \item Prof. G. Schmidt (DFT + financial support)
- \item Dr. E. Rauls (DFT + SiC)
+ \item Prof. J. Lindner
+ \item Prof. G. Schmidt
+ \item Dr. E. Rauls
\end{itemize}
+\vspace{ 0.2cm}
+
\begin{center}
\framebox{
-\bf Thank you for your attention!
+\normalsize\bf Thank you for your attention!
}
\end{center}
\end{slide}
+\begin{slide}
+
+\headphd
+ {\large\bf
+ Polytypes of SiC\\[0.6cm]
+ }
+
+\vspace{0.6cm}
+
+\includegraphics[width=3.8cm]{cubic_hex.eps}\\
+\begin{minipage}{1.9cm}
+{\tiny cubic (twist)}
+\end{minipage}
+\begin{minipage}{2.9cm}
+{\tiny hexagonal (no twist)}
+\end{minipage}
+
+\begin{picture}(0,0)(-150,0)
+ \includegraphics[width=7cm]{polytypes.eps}
+\end{picture}
+
+\vspace{0.6cm}
+
+\footnotesize
+
+\begin{tabular}{l c c c c c c}
+\hline
+ & 3C-SiC & 4H-SiC & 6H-SiC & Si & GaN & Diamond\\
+\hline
+Hardness [Mohs] & \multicolumn{3}{c}{------ 9.6 ------}& 6.5 & - & 10 \\
+Band gap [eV] & 2.36 & 3.23 & 3.03 & 1.12 & 3.39 & 5.5 \\
+Break down field [$10^6$ V/cm] & 4 & 3 & 3.2 & 0.6 & 5 & 10 \\
+Saturation drift velocity [$10^7$ cm/s] & 2.5 & 2.0 & 2.0 & 1 & 2.7 & 2.7 \\
+Electron mobility [cm$^2$/Vs] & 800 & 900 & 400 & 1100 & 900 & 2200 \\
+Hole mobility [cm$^2$/Vs] & 320 & 120 & 90 & 420 & 150 & 1600 \\
+Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\
+\hline
+\end{tabular}
+
+\begin{pspicture}(0,0)(0,0)
+\psellipse[linecolor=green](5.7,2.05)(0.4,0.50)
+\end{pspicture}
+\begin{pspicture}(0,0)(0,0)
+\psellipse[linecolor=green](5.6,0.89)(0.4,0.20)
+\end{pspicture}
+\begin{pspicture}(0,0)(0,0)
+\psellipse[linecolor=red](10.45,0.42)(0.4,0.20)
+\end{pspicture}
+
+\end{slide}
+
\end{document}
projects / lectures / latex.git / blobdiff