X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=blobdiff_plain;f=posic%2Ftalks%2Fdefense.tex;h=5ac85d61c7c72c105c2a5991e4ea3153c1787acb;hp=d41cff2b11d5c561eaf5aafe5503718fd8931aac;hb=b75fa3911c13c302a90ce982430815d709159419;hpb=17d5c879c418790a154098e51c524eca183c4d98

diff --git a/posic/talks/defense.tex b/posic/talks/defense.tex
index d41cff2..5ac85d6 100644
--- a/posic/talks/defense.tex
+++ b/posic/talks/defense.tex
@@ -248,101 +248,6 @@ E\\
 
 % fabrication
 
-\ifnum1=0
-\begin{slide}
-
-\headphd
- {\large\bf
-  Fabrication of silicon carbide
- }
-
- \small
- 
- \vspace{2pt}
-
-\begin{center}
- {\color{gray}
- \emph{Silicon carbide --- Born from the stars, perfected on earth.}
- }
-\end{center}
-
-\vspace{2pt}
-
-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
-       \underline{\foreignlanguage{greek}{a}-SiC}
- \item Production of favored \underline{3C-SiC} material
-       \underline{less advanced}
- \item Quality and size not yet sufficient
-\end{itemize}
-\begin{picture}(0,0)(-310,-20)
-  \includegraphics[width=2.0cm]{cree.eps}
-\end{picture}
-
-\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}
-
-\vspace{0.1cm}
-
-{\bf Alternative approach}\\
-Ion beam synthesis (IBS) of burried 3C-SiC layers in Si\hkl(1 0 0)
-
-\vspace{0.1cm}
-
-\scriptsize
-
-\framebox{
-\begin{minipage}{3.15cm}
- \begin{center}
-\includegraphics[width=3cm]{imp.eps}\\
- {\tiny
-  Carbon implantation
- }
- \end{center}
-\end{minipage}
-\begin{minipage}{3.15cm}
- \begin{center}
-\includegraphics[width=3cm]{annealing.eps}\\
- {\tiny
- Postannealing at $>$ \degc{1200}
- }
- \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}
-
-%\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}
 
 \headphd
@@ -379,32 +284,34 @@ Ion beam synthesis (IBS) of burried 3C-SiC layers in Si\hkl(1 0 0)
 \end{center}
 \end{minipage}
 \begin{minipage}{5cm}
+\begin{center}
 \begin{pspicture}(0,0)(0,0)
 \rnode{box}{
 \psframebox[fillstyle=solid,fillcolor=white,linecolor=blue,linestyle=solid]{
-\begin{minipage}{5.3cm}
+\begin{minipage}{3.3cm}
  \begin{center}
  {\color{blue}
   3C-SiC precipitation\\
   not yet fully understood
  }
  \end{center}
- \vspace*{0.1cm}
- \renewcommand\labelitemi{$\Rightarrow$}
- 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
- \end{itemize}
+% \vspace*{0.1cm}
+% \renewcommand\labelitemi{$\Rightarrow$}
+% 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
+% \end{itemize}
 \end{minipage}
 }}
-\rput(-6.8,5.5){\pnode{h0}}
-\rput(-3.0,5.5){\pnode{h1}}
+\rput(-5.3,5.5){\pnode{h0}}
+\rput(-1.95,5.5){\pnode{h1}}
 \ncline[linecolor=blue]{-}{h0}{h1}
 \ncline[linecolor=blue]{->}{h1}{box}
 \end{pspicture}
+\end{center}
 \end{minipage}
 
 \end{slide}
@@ -648,11 +555,11 @@ r = \unit[2--4]{nm}
  \end{itemize}
  $\Rightarrow$ mobile {\color{red}\ci} opposed to
  stable {\color{blue}\cs{}} configurations
-\item Strained silicon \& Si$_{1-y}$C$_y$ heterostructures
+\item Strained Si$_{1-y}$C$_y$/Si heterostructures
       {\tiny\color{gray}/Strane~et~al./Guedj~et~al./}
  \begin{itemize}
-  \item Initial {\color{blue}coherent} SiC precipitates (tensile strain)
-  \item Incoherent SiC (strain relaxation)
+  \item Initial {\color{blue}coherent} SiC structures (tensile strain)
+  \item Incoherent SiC nanocrystals (strain relaxation)
  \end{itemize}
 \end{itemize}
 \vspace{0.1cm}
@@ -846,13 +753,13 @@ $
 \end{minipage}
 \end{minipage}
 
-\vspace{0.2cm}
+\vspace{0.3cm}
 
-\begin{minipage}[b]{6cm}
+\begin{minipage}[t]{6cm}
 {\bf Defect formation energy}\\
 \framebox{
-$E_{\text{f}}=E-\sum_i N_i\mu_i$}\\[0.1cm]
-Particle reservoir: Si \& SiC\\[0.2cm]
+$E_{\text{f}}=E-\sum_i N_i\mu_i$}\\[0.5cm]
+%Particle reservoir: Si \& SiC\\[0.2cm]
 {\bf Binding energy}\\
 \framebox{
 $
@@ -866,7 +773,8 @@ $
 $E_{\text{b}}<0$: energetically favorable configuration\\
 $E_{\text{b}}\rightarrow 0$: non-interacting, isolated defects\\
 \end{minipage}
-\begin{minipage}[b]{6cm}
+\begin{minipage}[t]{6cm}
+\vspace{1.4cm}
 {\bf Migration barrier}
 \footnotesize
 \begin{itemize}
@@ -966,7 +874,7 @@ $E_{\text{f}}=5.18\text{ eV}$\\
 
 \scriptsize
 
-\vspace{0.2cm}
+\vspace{0.3cm}
 
 \begin{minipage}{6.8cm}
 \framebox{\hkl[0 0 -1] $\rightarrow$ \hkl[0 0 1]}\\
@@ -985,14 +893,14 @@ $\rightarrow$
 \begin{minipage}{2.0cm}
 \includegraphics[width=2.0cm]{c_pd_vasp/100_next_2333.eps}
 \end{minipage}\\[0.1cm]
-Spin polarization\\
-$\Rightarrow$ BC configuration constitutes local minimum\\
+Symmetry:\\
+$\Rightarrow$ Sufficient to consider \hkl[00-1] to BC transition\\
 $\Rightarrow$ Migration barrier to reach BC | $\Delta E=\unit[1.2]{eV}$
 \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}\\[0.3cm]
+\end{minipage}\\[0.4cm]
 %\hrule
 %
 \begin{minipage}{6.8cm}
@@ -1056,7 +964,7 @@ Note: Change in orientation
 \begin{itemize}
  \item Bond-centered configuration unstable\\
        $\rightarrow$ \ci{} \hkl<1 1 0> dumbbell
- \item Minima of the \hkl[0 0 -1] to \hkl[0 -1 0] transition\\
+ \item Minimum of the \hkl[0 0 -1] to \hkl[0 -1 0] transition\\
        $\rightarrow$ \ci{} \hkl<1 1 0> DB
 \end{itemize}
 \vspace{0.1cm}
@@ -1083,7 +991,7 @@ Note: Change in orientation
 
 \headphd
 {\large\bf\boldmath
- Defect combinations
+ Defect combinations --- ab inito
 }
 
 \footnotesize
@@ -1561,7 +1469,7 @@ $\rightarrow$ Consider $V_2$ and $V_3$
 \begin{minipage}{6.1cm}
 \scriptsize
 \underline{Low C concentration --- {\color{red}$V_1$}}\\[0.1cm]
-\hkl<1 0 0> C-Si dumbbell dominated structure
+\ci{} \hkl<1 0 0> dumbbell dominated structure
 \begin{itemize}
  \item Si-C bumbs around \unit[0.19]{nm}
  \item C-C peak at \unit[0.31]{nm} (expected in 3C-SiC):\\
@@ -1573,7 +1481,7 @@ $\rightarrow$ Consider $V_2$ and $V_3$
 \begin{minipage}{6cm}
 \centering
 Formation of \ci{} dumbbells\\
-C atoms in proper 3C-SiC distance first
+C atoms separated as expected in 3C-SiC
 \end{minipage}
 }}
 \end{pspicture}\\[0.1cm]
@@ -1621,7 +1529,7 @@ Amorphous SiC-like phase
 \begin{minipage}{6.1cm}
 \scriptsize
 \underline{Low C concentration --- {\color{red}$V_1$}}\\[0.1cm]
-\hkl<1 0 0> C-Si dumbbell dominated structure
+\ci{} \hkl<1 0 0> dumbbell dominated structure
 \begin{itemize}
  \item Si-C bumbs around \unit[0.19]{nm}
  \item C-C peak at \unit[0.31]{nm} (expected in 3C-SiC):\\
@@ -1633,7 +1541,7 @@ Amorphous SiC-like phase
 \begin{minipage}{6cm}
 \centering
 Formation of \ci{} dumbbells\\
-C atoms in proper 3C-SiC distance first
+C atoms separated as expected in 3C-SiC
 \end{minipage}
 }}
 \end{pspicture}\\[0.1cm]
@@ -1692,7 +1600,7 @@ No rearrangement/transition into 3C-SiC
 \vspace{0.2cm}
 
 {\bf Time scale problem of MD}\\[0.2cm]
-Precise integration \& thermodynamic sampling\\
+Minimize integration error \& precise thermodynamic sampling\\
 $\Rightarrow$ $\Delta t \ll \left( \max{\omega} \right)^{-1}$,
               $\omega$: vibrational mode\\
 $\Rightarrow$ {\color{red}\underline{Slow}} phase space propagation\\[0.2cm]
@@ -1708,8 +1616,7 @@ $\Rightarrow$ Phase transition consists of {\color{red}\underline{many}}
 
 {\bf Limitations related to the short range potential}\\[0.2cm]
 Cut-off function limits interaction to next neighbours\\
-$\Rightarrow$ Overestimated unphysical high forces of next neighbours
-              (factor: 2.4--3.4)
+$\Rightarrow$ Overestimated diffusion barrier (factor: 2.4--3.4)
 
 \vspace{1.4cm}
 
@@ -1776,7 +1683,8 @@ equilibrium properties
  \underline{Si-C bonds:}
  \begin{itemize}
   \item Vanishing cut-off artifact (above $1650\,^{\circ}\mathrm{C}$)
-  \item Structural change: C-Si \hkl<1 0 0> $\rightarrow$ C$_{\text{sub}}$
+  \item Structural change: \ci{} \hkl<1 0 0> DB $\rightarrow$
+        {\color{blue}\cs{}}
  \end{itemize}
  \underline{Si-Si bonds:}
  {\color{blue}Si-C$_{\text{sub}}$-Si} along \hkl<1 1 0>
@@ -1784,17 +1692,11 @@ equilibrium properties
  \underline{C-C bonds:}
  \begin{itemize}
   \item C-C next neighbour pairs reduced (mandatory)
-  \item Peak at 0.3 nm slightly shifted
-        \begin{itemize}
-         \item C-Si \hkl<1 0 0> combinations (dashed arrows)\\
-               $\rightarrow$ C-Si \hkl<1 0 0> \& C$_{\text{sub}}$
-               combinations (|)\\
-               $\rightarrow$ pure {\color{blue}C$_{\text{sub}}$ combinations}
-               ($\downarrow$)
-         \item Range [|-$\downarrow$]:
-               {\color{blue}C$_{\text{sub}}$ \& C$_{\text{sub}}$
-               with nearby Si$_{\text{I}}$}
-        \end{itemize}
+  \item Peak at 0.3 nm slightly shifted\\[0.05cm]
+        $\searrow$ \ci{} combinations (dashed arrows)\\
+        $\nearrow$ \ci{} \hkl<1 0 0> \& {\color{blue}\cs{} combinations} (|)\\
+        $\nearrow$ \ci{} pure \cs{} combinations ($\downarrow$)\\[0.05cm]
+        Range [|-$\downarrow$]: {\color{blue}\cs{} \& \cs{} with nearby \si}
  \end{itemize}
 \end{minipage}
 
@@ -1826,7 +1728,8 @@ equilibrium properties
  \underline{Si-C bonds:}
  \begin{itemize}
   \item Vanishing cut-off artifact (above $1650\,^{\circ}\mathrm{C}$)
-  \item Structural change: C-Si \hkl<1 0 0> $\rightarrow$ C$_{\text{sub}}$
+  \item Structural change: \ci{} \hkl<1 0 0> DB $\rightarrow$
+        {\color{blue}\cs{}}
  \end{itemize}
  \underline{Si-Si bonds:}
  {\color{blue}Si-C$_{\text{sub}}$-Si} along \hkl<1 1 0>
@@ -1834,17 +1737,11 @@ equilibrium properties
  \underline{C-C bonds:}
  \begin{itemize}
   \item C-C next neighbour pairs reduced (mandatory)
-  \item Peak at 0.3 nm slightly shifted
-        \begin{itemize}
-         \item C-Si \hkl<1 0 0> combinations (dashed arrows)\\
-               $\rightarrow$ C-Si \hkl<1 0 0> \& C$_{\text{sub}}$
-               combinations (|)\\
-               $\rightarrow$ pure {\color{blue}C$_{\text{sub}}$ combinations}
-               ($\downarrow$)
-         \item Range [|-$\downarrow$]:
-               {\color{blue}C$_{\text{sub}}$ \& C$_{\text{sub}}$
-               with nearby Si$_{\text{I}}$}
-        \end{itemize}
+  \item Peak at 0.3 nm slightly shifted\\[0.05cm]
+        $\searrow$ \ci{} combinations (dashed arrows)\\
+        $\nearrow$ \ci{} \hkl<1 0 0> \& {\color{blue}\cs{} combinations} (|)\\
+        $\nearrow$ \ci{} pure \cs{} combinations ($\downarrow$)\\[0.05cm]
+        Range [|-$\downarrow$]: {\color{blue}\cs{} \& \cs{} with nearby \si}
  \end{itemize}
 \end{minipage}
 
@@ -1865,9 +1762,14 @@ equilibrium properties
 {\Huge$\lightning$} {\color{red}\ci{}} --- vs --- {\color{blue}\cs{}} {\Huge$\lightning$}\\
 \end{center}
 \begin{itemize}
-\item Stretched coherent SiC structures\\
-$\Rightarrow$ Precipitation process involves {\color{blue}\cs}
-\item Role of \si{}
+\item Stretched coherent SiC structures directly observed\\
+\psframebox[linecolor=blue,linewidth=0.05cm]{
+\begin{minipage}{7cm}
+\centering
+\cs{} involved in the precipitation mechanism\\
+\end{minipage}
+}
+\item Emission of \si{} serves several needs:
       \begin{itemize}
        \item Vehicle to rearrange \cs --- [\cs{} \& \si{} $\leftrightarrow$ \ci]
        \item Building block for surrounding Si host \& further SiC
@@ -1880,16 +1782,13 @@ $\Rightarrow$ Precipitation process involves {\color{blue}\cs}
        \item Low T: highly mobile {\color{red}\ci}
        \item High T: stable configurations of {\color{blue}\cs}
       \end{itemize}
-\end{itemize}
-\vspace{0.2cm}
-\centering
 \psframebox[linecolor=blue,linewidth=0.05cm]{
 \begin{minipage}{7cm}
 \centering
-Precipitation mechanism involving \cs\\
 High T $\leftrightarrow$ IBS conditions far from equilibrium\\
 \end{minipage}
 }
+\end{itemize}
 \end{minipage}
 \vspace{0.2cm}
 }}
@@ -1969,9 +1868,6 @@ High C \& low T implants
 % skip high c conc
 \fi
 
-% for preparation
-%\fi
-
 \begin{slide}
 
 \headphd
@@ -1994,7 +1890,7 @@ High C \& low T implants
          \item Identified \ci{} migration path
          \item EA drastically overestimates the diffusion barrier
         \end{itemize}
-   \item Combinations of defects
+   \item Combinations of defects (DFT)
          \begin{itemize}
           \item Agglomeration of point defects energetically favorable
           \item C$_{\text{sub}}$ favored conditions (conceivable in IBS)
@@ -2013,7 +1909,7 @@ High C \& low T implants
   \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 Increased participation of \cs{} in the precipitation process
+  \item \cs{} involved in the precipitation process at elevated temperatures
   \item \si{}: vehicle to form \cs{} \& supply of Si \& stress compensation
         (stretched SiC, interface)
  \end{itemize}
@@ -2022,7 +1918,7 @@ High C \& low T implants
 
 \begin{center}
 {\color{blue}\bf
-\framebox{Precipitation by successive agglomeration of \cs{}}
+\framebox{IBS: 3C-SiC precipitation occurs by successive agglomeration of \cs{}}
 }
 \end{center}
 
@@ -2041,10 +1937,12 @@ High C \& low T implants
 
  Thanks to \ldots
 
+\begin{minipage}[t]{6cm}
  \underline{Augsburg}
  \begin{itemize}
   \item Prof. B. Stritzker
   \item Ralf Utermann
+  \item EP \RM{4}
  \end{itemize}
  
  \underline{Helsinki}
@@ -2063,17 +1961,30 @@ High C \& low T implants
   \item Prof. G. Schmidt
   \item Dr. E. Rauls
  \end{itemize}
+\end{minipage}
+\begin{minipage}[t]{6cm}
+\underline{Referees}
+ \begin{itemize}
+  \item PD V. Eyert
+  \item Prof. F. Haider
+ \end{itemize}
+\end{minipage}
 
-\vspace{ 0.2cm}
-
+\vspace{0.5cm}
 \begin{center}
 \framebox{
-\normalsize\bf Thank you for your attention!
+\Large\bf Thank you for your attention!
 }
 \end{center}
 
 \end{slide}
 
+
+
+
+
+
+
 \begin{slide}
 
 \headphd