\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
+\usepackage{stmaryrd}
\usepackage{latexsym}
\usepackage{ae}
\usepackage{pstricks}
\usepackage{pst-node}
+\usepackage{pst-grad}
%\usepackage{epic}
%\usepackage{eepic}
\usepackage{upgreek}
+\newcommand{\headdiplom}{
+\begin{pspicture}(0,0)(0,0)
+\rput(6.0,0.2){\psframebox[fillstyle=gradient,gradbegin=red,gradend=white,gradlines=1000,gradmidpoint=1,linestyle=none]{
+\begin{minipage}{14cm}
+\hfill
+\vspace{0.7cm}
+\end{minipage}
+}}
+\end{pspicture}
+}
+
+\newcommand{\headphd}{
+\begin{pspicture}(0,0)(0,0)
+\rput(6.0,0.2){\psframebox[fillstyle=gradient,gradbegin=blue,gradend=white,gradlines=1000,gradmidpoint=1,linestyle=none]{
+\begin{minipage}{14cm}
+\hfill
+\vspace{0.7cm}
+\end{minipage}
+}}
+\end{pspicture}
+}
+
\begin{document}
\extraslideheight{10in}
\end{center}
\end{slide}
+% no vertical centering
+\centerslidesfalse
+
\ifnum1=0
% intro
\begin{slide}
+\vspace*{1.8cm}
+
\small
\begin{pspicture}(0,0)(13.5,5)
\end{slide}
-\fi
% fabrication
\begin{slide}
\vspace{2pt}
+\begin{center}
{\color{gray}
\emph{Silicon carbide --- Born from the stars, perfected on earth.}
}
+\end{center}
\vspace{2pt}
-SiC thin film by MBE \& CVD
+SiC thin films by MBE \& CVD
\begin{itemize}
\item Much progress achieved in homo/heteroepitaxial SiC thin film growth
\item \underline{Commercially available} semiconductor power devices based on
\includegraphics[width=2.0cm]{cree.eps}
\end{picture}
-Alternative method: Ion beam synthesis of SiC in Si
+\vspace{-0.2cm}
- \begin{itemize}
- \item \underline{Sublimation growth using the modified Lely method}
- \begin{itemize}
- \item SiC single-crystalline seed at $T=1800 \, ^{\circ} \text{C}$
- \item Surrounded by polycrystalline SiC in a graphite crucible\\
- at $T=2100-2400 \, ^{\circ} \text{C}$
- \item Deposition of supersaturated vapor on cooler seed crystal
- \end{itemize}
- \item \underline{Homoepitaxial growth using CVD}
- \begin{itemize}
- \item Step-controlled epitaxy on off-oriented 6H-SiC substrates
- \item C$_3$H$_8$/SiH$_4$/H$_2$ at $1100-1500 \, ^{\circ} \text{C}$
- \item Angle, temperature $\rightarrow$ 3C/6H/4H-SiC
- \end{itemize}
- \item \underline{Heteroepitaxial growth of 3C-SiC on Si using CVD/MBE}
- \begin{itemize}
- \item Two steps: carbonization and growth
- \item $T=650-1050 \, ^{\circ} \text{C}$
- \item SiC/Si lattice mismatch $\approx$ 20 \%
- \item Quality and size not yet sufficient
- \end{itemize}
- \end{itemize}
+Alternative approach:
+Ion beam synthesis (IBS) of burried 3C-SiC layers in Si\hkl(1 0 0)
- \begin{picture}(0,0)(-280,-65)
- \includegraphics[width=3.8cm]{6h-sic_3c-sic.eps}
- \end{picture}
- \begin{picture}(0,0)(-280,-55)
- \begin{minipage}{5cm}
- {\tiny
- NASA: 6H-SiC and 3C-SiC LED\\[-7pt]
- on 6H-SiC substrate
- }
- \end{minipage}
- \end{picture}
- \begin{picture}(0,0)(-265,-150)
- \includegraphics[width=2.4cm]{m_lely.eps}
- \end{picture}
- \begin{picture}(0,0)(-333,-175)
- \begin{minipage}{5cm}
- {\tiny
- 1. Lid\\[-7pt]
- 2. Heating\\[-7pt]
- 3. Source\\[-7pt]
- 4. Crucible\\[-7pt]
- 5. Insulation\\[-7pt]
- 6. Seed crystal
- }
- \end{minipage}
- \end{picture}
- \begin{picture}(0,0)(-230,-35)
- \framebox{
- {\footnotesize\color{blue}\bf Hex: micropipes along c-axis}
+\vspace{0.2cm}
+
+\scriptsize
+
+\framebox{
+\begin{minipage}{3.15cm}
+ \begin{center}
+\includegraphics[width=3cm]{imp.eps}\\
+ {\tiny
+ Carbon implantation
}
- \end{picture}
- \begin{picture}(0,0)(-230,-10)
- \framebox{
- \begin{minipage}{3cm}
- {\footnotesize\color{blue}\bf 3C-SiC fabrication\\
- less advanced}
- \end{minipage}
+ \end{center}
+\end{minipage}
+\begin{minipage}{3.15cm}
+ \begin{center}
+\includegraphics[width=3cm]{annealing.eps}\\
+ {\tiny
+ \unit[12]{h} annealing at \degc{1200}
}
- \end{picture}
+ \end{center}
+\end{minipage}
+}
+\begin{minipage}{5.5cm}
+ \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}
\end{slide}
-\end{document}
-\ifnum1=0
-
% contents
\begin{slide}
+{\large\bf
+ Systematic investigation of C implantations into Si
+}
+
+\vspace{1.7cm}
+\begin{center}
+\hspace{-1.0cm}
+\includegraphics[width=0.75\textwidth]{imp_inv.eps}
+\end{center}
+
+\end{slide}
+
+% outline
+
+\begin{slide}
+
{\large\bf
Outline
}
- \begin{itemize}
- \item Implantation of C in Si --- Overview of experimental observations
- \item Utilized simulation techniques and modeled problems
- \begin{itemize}
- \item {\color{blue}Diploma thesis}\\
- \underline{Monte Carlo} simulations
- modeling the selforganization process
- leading to periodic arrays of nanometric amorphous SiC
- precipitates
- \item {\color{blue}Doctoral studies}\\
- Classical potential \underline{molecular dynamics} simulations
- \ldots\\
- \underline{Density functional theory} calculations
- \ldots\\[0.2cm]
- \ldots on defects and SiC precipitation in Si
- \end{itemize}
- \item Summary / Conclusion / Outlook
- \end{itemize}
+\vspace{1.7cm}
+\begin{center}
+\hspace{-1.0cm}
+\includegraphics[width=0.75\textwidth]{imp_inv.eps}
+\end{center}
+
+\begin{pspicture}(0,0)(0,0)
+\rput(6.0,7.0){\rnode{init}{\psframebox[fillstyle=gradient,gradbegin=red,gradend=white,gradlines=1000,gradmidpoint=1.0,linestyle=none]{
+\begin{minipage}{11cm}
+{\color{black}Diploma thesis}\\
+ \underline{Monte Carlo} simulation modeling the selforganization process\\
+ leading to periodic arrays of nanometric amorphous SiC precipitates
+\end{minipage}
+}}}
+\end{pspicture}
+\begin{pspicture}(0,0)(0,0)
+\rput(6.0,-0.5){\rnode{init}{\psframebox[fillstyle=gradient,gradbegin=blue,gradend=white,gradmidpoint=1.0,gradlines=1000,linestyle=none]{
+\begin{minipage}{11cm}
+{\color{black}Doctoral studies}\\
+ Classical potential \underline{molecular dynamics} simulations \ldots\\
+ \underline{Density functional theory} calculations \ldots\\[0.2cm]
+ \ldots on defect formation and SiC precipitation in Si
+\end{minipage}
+}}}
+\end{pspicture}
+\begin{pspicture}(0,0)(0,0)
+\psellipse[linecolor=red,linewidth=0.05cm](5,3.0)(0.8,1.0)
+\end{pspicture}
+\begin{pspicture}(0,0)(0,0)
+\psellipse[linecolor=blue,linewidth=0.05cm](8.2,3.2)(1.5,1.6)
+\end{pspicture}
\end{slide}
+\begin{slide}
+\headdiplom
+{\large\bf
+ Selforganization of nanometric amorphous SiC lamellae
+}
-\end{document}
+\small
+
+\vspace{0.2cm}
+
+\begin{itemize}
+ \item Regularly spaced, nanometric spherical\\
+ and lamellar amorphous inclusions\\
+ at the upper a/c interface
+ \item Carbon accumulation\\
+ in amorphous volumes
+\end{itemize}
+
+\vspace{0.4cm}
+
+\begin{minipage}{12cm}
+\includegraphics[width=9cm]{../../nlsop/img/k393abild1_e_l.eps}\\
+{\scriptsize
+XTEM bright-field, \unit[180]{keV} C$^+ \rightarrow$ Si,
+{\color{red}\underline{\degc{150}}},
+Dose: \unit[4.3 $\times 10^{17}$]{cm$^{-2}$}
+}
+\end{minipage}
+
+\begin{picture}(0,0)(-182,-215)
+\begin{minipage}{6.5cm}
+\begin{center}
+\includegraphics[width=6.5cm]{../../nlsop/img/eftem.eps}\\[-0.2cm]
+{\scriptsize
+XTEM bright-field and respective EFTEM C map
+}
+\end{center}
+\end{minipage}
+\end{picture}
+
+\end{slide}
\begin{slide}
- {\large\bf
- Fabrication of silicon carbide
- }
+\headdiplom
+{\large\bf
+ Model displaying the formation of ordered lamellae
+}
- \small
+\vspace{0.1cm}
- Alternative approach:
- Ion beam synthesis (IBS) of burried 3C-SiC layers in Si\hkl(1 0 0)
- \begin{itemize}
- \item \underline{Implantation step 1}\\
- 180 keV C$^+$, $D=7.9\times 10^{17}$ cm$^{-2}$, $T_{\text{i}}=500\,^{\circ}\mathrm{C}$\\
- $\Rightarrow$ box-like distribution of equally sized
- and epitactically oriented SiC precipitates
-
- \item \underline{Implantation step 2}\\
- 180 keV C$^+$, $D=0.6\times 10^{17}$ cm$^{-2}$, $T_{\text{i}}=250\,^{\circ}\mathrm{C}$\\
- $\Rightarrow$ destruction of SiC nanocrystals
- in growing amorphous interface layers
- \item \underline{Annealing}\\
- $T=1250\,^{\circ}\mathrm{C}$, $t=10\,\text{h}$\\
- $\Rightarrow$ homogeneous, stoichiometric SiC layer
- with sharp interfaces
- \end{itemize}
+\begin{center}
+ \includegraphics[width=8.0cm]{../../nlsop/img/modell_ng_e.eps}
+\end{center}
- \begin{minipage}{6.3cm}
- \includegraphics[width=6cm]{ibs_3c-sic.eps}\\[-0.2cm]
- {\tiny
- XTEM micrograph of single crystalline 3C-SiC in Si\hkl(1 0 0)
- }
- \end{minipage}
+\footnotesize
+
+\begin{itemize}
+\item Supersaturation of C in c-Si\\
+ $\rightarrow$ {\bf Carbon induced} nucleation of spherical
+ SiC$_x$-precipitates
+\item High interfacial energy between 3C-SiC and c-Si\\
+ $\rightarrow$ {\bf Amorphous} precipitates
+\item \unit[20-- 30]{\%} lower silicon density of a-SiC$_x$ compared to c-Si\\
+ $\rightarrow$ {\bf Lateral strain} (black arrows)
+\item Implantation range near surface\\
+ $\rightarrow$ {\bf Relaxation} of {\bf vertical strain component}
+\item Reduction of the carbon supersaturation in c-Si\\
+ $\rightarrow$ {\bf Carbon diffusion} into amorphous volumina
+ (white arrows)
+\item Remaining lateral strain\\
+ $\rightarrow$ {\bf Strain enhanced} lateral amorphisation
+\item Absence of crystalline neighbours (structural information)\\
+ $\rightarrow$ {\bf Stabilization} of amorphous inclusions
+ {\bf against recrystallization}
+\end{itemize}
+
+\end{slide}
+
+\begin{slide}
+
+\headdiplom
+{\large\bf
+ Implementation of the Monte Carlo code
+}
+
+\small
+
+\begin{enumerate}
+ \item \underline{Amorphization / Recrystallization}\\
+ Ion collision in discretized target determined by random numbers
+ distributed according to nuclear energy loss.
+ Amorphization/recrystallization probability:
+\[
+p_{c \rightarrow a}(\vec{r}) = {\color{green} p_b} + {\color{blue} p_c c_C(\vec{r})} + {\color{red} \sum_{\textrm{amorphous neighbours}} \frac{p_s c_C(\vec{r'})}{(r-r')^2}}
+\]
+\begin{itemize}
+ \item {\color{green} $p_b$} normal `ballistic' amorphization
+ \item {\color{blue} $p_c$} carbon induced amorphization
+ \item {\color{red} $p_s$} stress enhanced amorphization
+\end{itemize}
+\[
+p_{a \rightarrow c}(\vec r) = (1 - p_{c \rightarrow a}(\vec r)) \Big(1 - \frac{\sum_{direct \, neighbours} \delta (\vec{r'})}{6} \Big) \, \textrm{,}
+\]
+\[
+\delta (\vec r) = \left\{
+\begin{array}{ll}
+ 1 & \textrm{if volume at position $\vec r$ is amorphous} \\
+ 0 & \textrm{otherwise} \\
+\end{array}
+\right.
+\]
+ \item \underline{Carbon incorporation}\\
+ Incorporation volume determined according to implantation profile
+ \item \underline{Diffusion / Sputtering}
+ \begin{itemize}
+ \item Transfer fraction of C atoms
+ of crystalline into neighbored amorphous volumes
+ \item Remove surface layer
+ \end{itemize}
+\end{enumerate}
+
+\end{slide}
+
+\begin{slide}
+
+\begin{minipage}{3.7cm}
+\begin{pspicture}(0,0)(0,0)
+\rput(1.7,0.2){\psframebox[fillstyle=gradient,gradbegin=red,gradend=white,gradlines=1000,gradangle=10,gradmidpoint=1,linestyle=none]{
+\begin{minipage}{3.7cm}
+\hfill
+\vspace{0.7cm}
+\end{minipage}
+}}
+\end{pspicture}
+{\large\bf
+ Results
+}
+
+\footnotesize
+
+\vspace{1.2cm}
+
+Evolution of the \ldots
+\begin{itemize}
+ \item continuous\\
+ amorphous layer
+ \item a/c interface
+ \item lamellar precipitates
+\end{itemize}
+\ldots reproduced!\\[1.4cm]
+
+{\color{blue}
+\begin{center}
+Experiment \& simulation\\
+in good agreement\\[1.0cm]
+
+Simulation is able to model the whole depth region\\[1.2cm]
+\end{center}
+}
+
+\end{minipage}
+\begin{minipage}{0.5cm}
+\vfill
+\end{minipage}
+\begin{minipage}{8.0cm}
+ \vspace{-0.3cm}
+ \includegraphics[width=9cm]{../../nlsop/img/dosis_entwicklung_ng_e_1-2.eps}\\
+ \includegraphics[width=9cm]{../../nlsop/img/dosis_entwicklung_ng_e2_2-2.eps}
+\end{minipage}
+
+\end{slide}
+
+\begin{slide}
+
+\headdiplom
+{\large\bf
+ Structural \& compositional details
+}
+
+\begin{minipage}[t]{7.5cm}
+\includegraphics[height=6.5cm]{../../nlsop/img/ac_cconc_ver2_e.eps}\\
+\end{minipage}
+\begin{minipage}[t]{5.0cm}
+\includegraphics[height=6.5cm]{../../nlsop/img/97_98_e.eps}
+\end{minipage}
+
+\footnotesize
+
+\vspace{-0.1cm}
+
+\begin{itemize}
+ \item Fluctuation of C concentration in lamellae region
+ \item \unit[8--10]{at.\%} C saturation limit
+ within the respective conditions
+ \item Complementarily arranged and alternating sequence of layers\\
+ with a high and low amount of amorphous regions
+ \item C accumulation in the amorphous phase / Origin of stress
+\end{itemize}
+
+\begin{picture}(0,0)(-260,-50)
\framebox{
- \begin{minipage}{6.3cm}
+\begin{minipage}{3cm}
+\begin{center}
+{\color{blue}
+Precipitation process\\
+gets traceable\\
+by simulation!
+}
+\end{center}
+\end{minipage}
+}
+\end{picture}
+
+\end{slide}
+
+\begin{slide}
+
+\headphd
+{\large\bf
+ Formation of epitaxial single crystalline 3C-SiC
+}
+
+\footnotesize
+
+\vspace{0.2cm}
+
+\begin{center}
+\begin{itemize}
+ \item \underline{Implantation step 1}\\[0.1cm]
+ Almost stoichiometric dose | \unit[180]{keV} | \degc{500}\\
+ $\Rightarrow$ Epitaxial {\color{blue}3C-SiC} layer \&
+ {\color{blue}precipitates}
+ \item \underline{Implantation step 2}\\[0.1cm]
+ Little remaining dose | \unit[180]{keV} | \degc{250}\\
+ $\Rightarrow$
+ Destruction/Amorphization of precipitates at layer interface
+ \item \underline{Annealing}\\[0.1cm]
+ \unit[10]{h} at \degc{1250}\\
+ $\Rightarrow$ Homogeneous 3C-SiC layer with sharp interfaces
+\end{itemize}
+\end{center}
+
+\begin{minipage}{7cm}
+\includegraphics[width=7cm]{ibs_3c-sic.eps}
+\end{minipage}
+\begin{minipage}{5cm}
+\begin{pspicture}(0,0)(0,0)
+\rnode{box}{
+\psframebox[fillstyle=solid,fillcolor=white,linecolor=blue,linestyle=solid]{
+\begin{minipage}{5.3cm}
\begin{center}
{\color{blue}
- Precipitation mechanism not yet fully understood!
+ 3C-SiC precipitation\\
+ not yet fully understood
}
+ \end{center}
+ \vspace*{0.1cm}
\renewcommand\labelitemi{$\Rightarrow$}
- \small
- \underline{Understanding the SiC precipitation}
+ Details of the SiC precipitation
\begin{itemize}
- \item significant technological progress in SiC thin film formation
- \item perspectives for processes relying upon prevention of SiC precipitation
+ \item significant technological progress\\
+ in SiC thin film formation
+ \item perspectives for processes relying\\
+ upon prevention of SiC precipitation
\end{itemize}
- \end{center}
- \end{minipage}
-}
-
-\end{slide}
+\end{minipage}
+}}
+\rput(-6.8,5.4){\pnode{h0}}
+\rput(-3.0,5.4){\pnode{h1}}
+\ncline[linecolor=blue]{-}{h0}{h1}
+\ncline[linecolor=blue]{->}{h1}{box}
+\end{pspicture}
+\end{minipage}
+\end{slide}
\begin{slide}
- {\large\bf
+\headphd
+{\large\bf
Supposed precipitation mechanism of SiC in Si
- }
+}
\scriptsize
\vspace{0.1cm}
- \begin{minipage}{3.8cm}
- Si \& SiC lattice structure\\[0.2cm]
- \includegraphics[width=3.5cm]{sic_unit_cell.eps}\\[-0.3cm]
- \hrule
+ \framebox{
+ \begin{minipage}{3.6cm}
+ \begin{center}
+ Si \& SiC lattice structure\\[0.1cm]
+ \includegraphics[width=2.3cm]{sic_unit_cell.eps}
+ \end{center}
+{\tiny
+ \begin{minipage}{1.7cm}
+\underline{Silicon}\\
+{\color{yellow}$\bullet$} Si | {\color{gray}$\bullet$} Si\\
+$a=\unit[5.429]{\\A}$\\
+$\rho^*_{\text{Si}}=\unit[100]{\%}$
+ \end{minipage}
+ \begin{minipage}{1.7cm}
+\underline{Silicon carbide}\\
+{\color{yellow}$\bullet$} Si | {\color{gray}$\bullet$} C\\
+$a=\unit[4.359]{\\A}$\\
+$\rho^*_{\text{Si}}=\unit[97]{\%}$
+ \end{minipage}
+}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ }
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
\includegraphics[width=3.3cm]{tem_c-si-db.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{tem_3c-sic.eps}
\end{center}
\end{minipage}
- \begin{minipage}{4cm}
+ \vspace{0.1cm}
+
+ \begin{minipage}{4.0cm}
\begin{center}
C-Si dimers (dumbbells)\\[-0.1cm]
on Si interstitial sites
\end{center}
\end{minipage}
- \hspace{0.2cm}
- \begin{minipage}{4.2cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
Agglomeration of C-Si dumbbells\\[-0.1cm]
$\Rightarrow$ dark contrasts
\end{center}
\end{minipage}
- \hspace{0.2cm}
- \begin{minipage}{4cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
Precipitation of 3C-SiC in Si\\[-0.1cm]
$\Rightarrow$ Moir\'e fringes\\[-0.1cm]
\end{center}
\end{minipage}
- \begin{minipage}{3.8cm}
+ \vspace{0.1cm}
+
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_01.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_02.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_03.eps}
\end{center}
\end{minipage}
\begin{pspicture}(0,0)(0,0)
-\psline[linewidth=4pt]{->}(8.5,2)(9.0,2)
-\psellipse[linecolor=blue](11.5,5.8)(0.3,0.5)
-\rput{-20}{\psellipse[linecolor=blue](3.3,8.1)(0.3,0.5)}
-\psline[linewidth=4pt]{->}(4.0,2)(4.5,2)
-\rput(12.7,0.3){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+\psline[linewidth=2pt]{->}(8.3,2)(8.8,2)
+\psellipse[linecolor=blue](11.1,6.0)(0.3,0.5)
+\rput{-20}{\psellipse[linecolor=blue](3.1,8.2)(0.3,0.5)}
+\psline[linewidth=2pt]{->}(3.9,2)(4.4,2)
+\rput(11.8,0.3){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
$4a_{\text{Si}}=5a_{\text{SiC}}$
}}}
-\rput(12.2,8){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+\rput(11.5,8){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
\hkl(h k l) planes match
}}}
-\rput(9.7,6.2){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
-r = 2 - 4 nm
+\rput(8.5,6.2){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+r = \unit[2--4]{nm}
}}}
\end{pspicture}
\begin{slide}
- {\large\bf
- Supposed precipitation mechanism of SiC in Si
- }
+\headphd
+{\large\bf
+ Supposed precipitation mechanism of SiC in Si
+}
\scriptsize
\vspace{0.1cm}
- \begin{minipage}{3.8cm}
- Si \& SiC lattice structure\\[0.2cm]
- \includegraphics[width=3.5cm]{sic_unit_cell.eps}\\[-0.3cm]
- \hrule
+ \framebox{
+ \begin{minipage}{3.6cm}
+ \begin{center}
+ Si \& SiC lattice structure\\[0.1cm]
+ \includegraphics[width=2.3cm]{sic_unit_cell.eps}
+ \end{center}
+{\tiny
+ \begin{minipage}{1.7cm}
+\underline{Silicon}\\
+{\color{yellow}$\bullet$} Si | {\color{gray}$\bullet$} Si\\
+$a=\unit[5.429]{\\A}$\\
+$\rho^*_{\text{Si}}=\unit[100]{\%}$
+ \end{minipage}
+ \begin{minipage}{1.7cm}
+\underline{Silicon carbide}\\
+{\color{yellow}$\bullet$} Si | {\color{gray}$\bullet$} C\\
+$a=\unit[4.359]{\\A}$\\
+$\rho^*_{\text{Si}}=\unit[97]{\%}$
+ \end{minipage}
+}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ }
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
\includegraphics[width=3.3cm]{tem_c-si-db.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{tem_3c-sic.eps}
\end{center}
\end{minipage}
- \begin{minipage}{4cm}
+ \vspace{0.1cm}
+
+ \begin{minipage}{4.0cm}
\begin{center}
C-Si dimers (dumbbells)\\[-0.1cm]
on Si interstitial sites
\end{center}
\end{minipage}
- \hspace{0.2cm}
- \begin{minipage}{4.2cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
Agglomeration of C-Si dumbbells\\[-0.1cm]
$\Rightarrow$ dark contrasts
\end{center}
\end{minipage}
- \hspace{0.2cm}
- \begin{minipage}{4cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
Precipitation of 3C-SiC in Si\\[-0.1cm]
$\Rightarrow$ Moir\'e fringes\\[-0.1cm]
\end{center}
\end{minipage}
- \begin{minipage}{3.8cm}
+ \vspace{0.1cm}
+
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_01.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.1cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_02.eps}
\end{center}
\end{minipage}
- \hspace{0.6cm}
- \begin{minipage}{3.8cm}
+ \hspace{0.1cm}
+ \begin{minipage}{4.0cm}
\begin{center}
\includegraphics[width=3.3cm]{sic_prec_seq_03.eps}
\end{center}
\end{minipage}
\begin{pspicture}(0,0)(0,0)
-\psline[linewidth=4pt]{->}(8.5,2)(9.0,2)
-\psellipse[linecolor=blue](11.5,5.8)(0.3,0.5)
-\rput{-20}{\psellipse[linecolor=blue](3.3,8.1)(0.3,0.5)}
-\psline[linewidth=4pt]{->}(4.0,2)(4.5,2)
-\rput(12.7,0.3){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+\psline[linewidth=2pt]{->}(8.3,2)(8.8,2)
+\psellipse[linecolor=blue](11.1,6.0)(0.3,0.5)
+\rput{-20}{\psellipse[linecolor=blue](3.1,8.2)(0.3,0.5)}
+\psline[linewidth=2pt]{->}(3.9,2)(4.4,2)
+\rput(11.8,0.3){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
$4a_{\text{Si}}=5a_{\text{SiC}}$
}}}
-\rput(12.2,8){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+\rput(11.5,8){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
\hkl(h k l) planes match
}}}
-\rput(9.7,6.2){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
-r = 2 - 4 nm
+\rput(8.5,6.2){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=hb]{
+r = \unit[2--4]{nm}
}}}
-\rput(6.7,5.2){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=white]{
+% controversial view!
+\rput(6.5,5.0){\psframebox[fillstyle=solid,opacity=0.5,fillcolor=black]{
+\begin{minipage}{14cm}
+\hfill
+\vspace{12cm}
+\end{minipage}
+}}
+\rput(6.5,5.3){\rnode{init}{\psframebox[fillstyle=solid,fillcolor=white,linewidth=0.1cm]{
\begin{minipage}{10cm}
\small
-{\color{red}\bf Controversial views}
+\vspace*{0.2cm}
+\begin{center}
+{\color{gray}\bf Controversial findings}
+\end{center}
\begin{itemize}
-\item Implantations at high T (Nejim et al.)
+\item High-temperature implantation {\tiny\color{gray}/Nejim~et~al./}
\begin{itemize}
- \item Topotactic transformation based on \cs
- \item \si{} as supply reacting with further C in cleared volume
+ \item C incorporated {\color{blue}substitutionally} on regular Si lattice sites
+ \item \si{} reacting with further C in cleared volume
\end{itemize}
-\item Annealing behavior (Serre et al.)
+\item Annealing behavior {\tiny\color{gray}/Serre~et~al./}
\begin{itemize}
- \item Room temperature implants $\rightarrow$ highly mobile C
- \item Elevated T implants $\rightarrow$ no/low C redistribution/migration\\
- (indicate stable \cs{} configurations)
+ \item Room temperature implantation $\rightarrow$ high C diffusion
+ \item Elevated temperature implantation $\rightarrow$ no C redistribution
\end{itemize}
+ $\Rightarrow$ mobile {\color{red}\ci} opposed to
+ stable {\color{blue}\cs{}} configurations
\item Strained silicon \& Si/SiC heterostructures
+ {\tiny\color{gray}/Strane~et~al./Guedj~et~al./}
\begin{itemize}
- \item Coherent SiC precipitates (tensile strain)
+ \item {\color{blue}Coherent} SiC precipitates (tensile strain)
\item Incoherent SiC (strain relaxation)
\end{itemize}
\end{itemize}
+\vspace{0.1cm}
+\begin{center}
+{\Huge${\lightning}$} \hspace{0.3cm}
+{\color{blue}\cs{}} --- vs --- {\color{red}\ci} \hspace{0.3cm}
+{\Huge${\lightning}$}
+\end{center}
+\vspace{0.2cm}
\end{minipage}
}}}
\end{pspicture}
\end{slide}
+% continue here
+\fi
+
\begin{slide}
- {\large\bf
- Molecular dynamics (MD) simulations
- }
+\headphd
+{\large\bf
+ Utilized computational methods
+}
- \vspace{12pt}
+ \vspace{0.1cm}
\small
- {\bf MD basics:}
+{\bf Molecular dynamics (MD):}\\
+\scriptsize
+\begin{tabular}{l r}
+\hline
+Basics & Details\\
+\hline
+Microscopic description of N particle system & \\
+Analytical interaction potential & Tersoff-like bond order potential (Erhart/Albe) \\
+Numerical integration using Newtons equation of motion as a propagation rule in 6N-dimensional phase space & Velocity Verlet | timestep: \unit[1]{fs} \\
+Observables obtained by time and/or ensemble averages & NpT (isothermal-isobaric)\\
+%\begin{itemize}
+%\item Berendsen thermostat:
+% $\tau_{\text{T}}=100\text{ fs}$
+%\item Berendsen barostat:\\
+% $\tau_{\text{P}}=100\text{ fs}$,
+% $\beta^{-1}=100\text{ GPa}$
+%\end{itemize}\\
+\hline
+\end{tabular}
+
\begin{itemize}
\item Microscopic description of N particle system
\item Analytical interaction potential
\end{slide}
+\end{document}
+\ifnum1=0
+
\begin{slide}
{\large\bf
projects / lectures / latex.git / blobdiff