X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=blobdiff_plain;f=posic%2Ftalks%2Fdefense.tex;h=2ae5461209d75b91dc221065859efd36b3ac678e;hp=c6cb981737d60be6dd44500d9fc438cc7cf10fef;hb=e3b7278cc861f9eda107e72ebd8f07f90056c3a8;hpb=a08cd67251d6433ee23653e567601260436c923a

diff --git a/posic/talks/defense.tex b/posic/talks/defense.tex
index c6cb981..2ae5461 100644
--- a/posic/talks/defense.tex
+++ b/posic/talks/defense.tex
@@ -122,6 +122,7 @@
 
 % layout check
 %\layout
+\ifnum1=0
 \begin{slide}
 \center
 {\Huge
@@ -134,6 +135,7 @@ F\\
 E\\
 }
 \end{slide}
+\fi
 
 % topic
 
@@ -170,7 +172,7 @@ E\\
 \centerslidesfalse
 
 % skip for preparation
-\ifnum1=0
+%\ifnum1=0
 
 % intro
 
@@ -244,62 +246,9 @@ E\\
 
 \end{slide}
 
-% motivation
-
-\begin{slide}
-
- {\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](5.7,2.10)(0.4,0.5)
-\end{pspicture}
-\begin{pspicture}(0,0)(0,0)
-\psellipse[linecolor=green](5.6,0.92)(0.4,0.2)
-\end{pspicture}
-\begin{pspicture}(0,0)(0,0)
-\psellipse[linecolor=red](10.45,0.45)(0.4,0.2)
-\end{pspicture}
-
-\end{slide}
-
-\fi
-
 % fabrication
 
+\ifnum1=0
 \begin{slide}
 
 \headphd
@@ -331,10 +280,20 @@ SiC thin films by MBE \& CVD
 \begin{picture}(0,0)(-310,-20)
   \includegraphics[width=2.0cm]{cree.eps}
 \end{picture}
-{\color{red}\scriptsize Mismatch in thermal expansion coeefficient
-                        and lattice paramater}
 
-\vspace{-0.2cm}
+\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)
@@ -362,15 +321,27 @@ Ion beam synthesis (IBS) of burried 3C-SiC layers in Si\hkl(1 0 0)
 \end{minipage}
 }
 \begin{minipage}{5.5cm}
-\begin{center}
-{\small
-No surface bending effects\\
-$\Rightarrow$ 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}
 
@@ -390,7 +361,7 @@ $\Rightarrow$ Synthesis of large area SiC films possible
         $\Rightarrow$ 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]
@@ -438,33 +409,6 @@ $\Rightarrow$ Synthesis of large area SiC films possible
 
 \end{slide}
 
-\end{document}
-% temp
-\ifnum1=0
-
-% contents
-
-\begin{slide}
-
-\headphd
-{\large\bf
- Outline
-}
-
- \begin{itemize}
-  \item Supposed precipitation mechanism of SiC in Si
-  \item Utilized simulation techniques
-        \begin{itemize}
-         \item Molecular dynamics (MD) simulations
-         \item Density functional theory (DFT) calculations
-        \end{itemize}
-  \item C and Si self-interstitial point defects in silicon
-  \item Silicon carbide precipitation simulations
-  \item Summary / Conclusion
- \end{itemize}
-
-\end{slide}
-
 \begin{slide}
 
 \headphd
@@ -516,7 +460,7 @@ $\rho^*_{\text{Si}}=\unit[97]{\%}$
  \begin{minipage}{4.0cm}
  \begin{center}
  C-Si dimers (dumbbells)\\[-0.1cm]
- on Si interstitial sites
+ on Si lattice sites
  \end{center}
  \end{minipage}
  \hspace{0.1cm}
@@ -694,7 +638,7 @@ r = \unit[2--4]{nm}
 \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./}
@@ -704,10 +648,10 @@ r = \unit[2--4]{nm}
  \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}
@@ -726,6 +670,35 @@ r = \unit[2--4]{nm}
 
 \begin{slide}
 
+% contents
+
+\headphd
+{\large\bf
+ Outline
+}
+
+ \begin{itemize}
+  {\color{gray}
+  \item Introduction / Motivation
+  \item Assumed SiC precipitation mechanisms / Controversy
+  }
+  \item Utilized simulation techniques
+        \begin{itemize}
+         \item Molecular dynamics (MD) simulations
+         \item Density functional theory (DFT) calculations
+        \end{itemize}
+  \item Simulation results
+        \begin{itemize}
+         \item C and Si self-interstitial point defects in silicon
+         \item Silicon carbide precipitation simulations
+        \end{itemize}
+  \item Summary / Conclusion
+ \end{itemize}
+
+\end{slide}
+
+\begin{slide}
+
 \headphd
 {\large\bf
  Utilized computational methods
@@ -774,7 +747,7 @@ NpT (isothermal-isobaric) | Berendsen thermostat/barostat\\
 \hrule
 \begin{itemize}
 \item Code: \textsc{vasp}
-\item Plane wave basis set
+\item Plane wave basis set | $E_{\text{cut}}=\unit[300]{eV}$
 %$\displaystyle
 %\Phi_i=\sum_{|G+k|<G_{\text{cut}}} c_{i,k+G} \exp{\left(i(k+G)r\right)}
 %$\\
@@ -1200,7 +1173,7 @@ $\Rightarrow$ $sp^2$ hybridization
 
 \scriptsize
 
-\vspace{0.1cm}
+\vspace{0.2cm}
 
 \begin{minipage}{6.8cm}
 \framebox{\hkl[0 0 -1] $\rightarrow$ \hkl[0 0 1]}\\
@@ -1225,7 +1198,8 @@ $\Rightarrow$ 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}\\[0.2cm]
+\end{minipage}\\[0.3cm]
 %\hrule
 %
 \begin{minipage}{6.8cm}
@@ -1253,9 +1227,9 @@ Note: Change in orientation
 \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}
 
@@ -2100,11 +2074,6 @@ equilibrium properties
 \begin{itemize}
 \item Stretched coherent SiC structures\\
 $\Rightarrow$ Precipitation process involves {\color{blue}\cs}
-\item Explains annealing behavior of high/low T C implantations
-      \begin{itemize}
-       \item Low T: highly mobile {\color{red}\ci}
-       \item High T: stable configurations of {\color{blue}\cs}
-      \end{itemize}
 \item Role of \si{}
       \begin{itemize}
        \item Vehicle to rearrange \cs --- [\cs{} \& \si{} $\leftrightarrow$ \ci]
@@ -2113,6 +2082,11 @@ $\Rightarrow$ Precipitation process involves {\color{blue}\cs}
              \ldots Si/SiC interface\\
              \ldots within stretched coherent SiC structure
       \end{itemize}
+\item Explains annealing behavior of high/low T C implantations
+      \begin{itemize}
+       \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
@@ -2130,7 +2104,7 @@ High T $\leftrightarrow$ IBS conditions far from equilibrium\\
 
 \end{slide}
 
-% skip high T / C conc ... only here!
+% skip high c conc results
 \ifnum1=0
 
 \begin{slide}
@@ -2141,10 +2115,10 @@ High T $\leftrightarrow$ IBS conditions far from equilibrium\\
 
 \footnotesize
 
-\begin{minipage}{6.5cm}
+\begin{minipage}{6.0cm}
 \includegraphics[width=6.4cm]{12_pc_thesis.ps}
 \end{minipage}
-\begin{minipage}{6.5cm}
+\begin{minipage}{6.0cm}
 \includegraphics[width=6.4cm]{12_pc_c_thesis.ps}
 \end{minipage}
 
@@ -2199,64 +2173,74 @@ High C \& low T implants
 
 \end{slide}
 
-% skipped high T / C conc
+% skip high c conc
 \fi
 
+% for preparation
+%\fi
+
 \begin{slide}
 
+\headphd
 {\large\bf
- Summary / Outlook
+ Summary and Conclusions
 }
 
-\small
+\footnotesize
 
-\begin{pspicture}(0,0)(12,1.0)
-\psframebox[fillstyle=gradient,gradbegin=hred,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
+\vspace{0.1cm}
+
+\framebox{
+\begin{minipage}{12.3cm}
+ \underline{Defects}
+ \begin{itemize}
+   \item DFT / EA
+        \begin{itemize}
+         \item Point defects excellently / fairly well described
+               by DFT / EA
+         \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
+          \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
+        \end{itemize}
+ \end{itemize}
 \end{minipage}
 }
-\end{pspicture}\\[0.4cm]
-\begin{pspicture}(0,0)(12,2)
-\psframebox[fillstyle=gradient,gradbegin=hblue,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
+
+\framebox{
+\begin{minipage}[t]{12.3cm}
+ \underline{Pecipitation simulations}
+ \begin{itemize}
+  \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 Increased participation of \cs{} in the precipitation process
+  \item \si{}: vehicle to form \cs{} \& supply of Si \& stress compensation
+        (stretched SiC, interface)
+ \end{itemize}
 \end{minipage}
 }
-\end{pspicture}\\[0.5cm]
-\begin{pspicture}(0,0)(12,3)
-\psframebox[fillstyle=solid,fillcolor=white,linestyle=solid]{
-\begin{minipage}{11cm}
-\vspace{0.2cm}
-{\color{black}\bf How to proceed \ldots}\\[0.1cm]
-MC $\rightarrow$ empirical potential MD $\rightarrow$ Ground-state DFT \ldots
-\begin{itemize}
- \renewcommand\labelitemi{$\ldots$}
- \item beyond LDA/GGA methods \& ground-state DFT
-\end{itemize}
-Investigation of structure \& structural evolution \ldots
-\begin{itemize}
- \renewcommand\labelitemi{$\ldots$}
- \item electronic/optical properties
- \item electronic correlations
- \item non-equilibrium systems
-\end{itemize}
-\end{minipage}
+
+\begin{center}
+{\color{blue}\bf
+\framebox{Precipitation by successive agglomeration of \cs{}}
 }
-\end{pspicture}\\[0.5cm]
+\end{center}
 
 \end{slide}
 
 \begin{slide}
 
- {\large\bf
-  Acknowledgements
- }
+\headphd
+{\large\bf
+ Acknowledgements
+}
 
  \vspace{0.1cm}
 
@@ -2266,36 +2250,87 @@ Investigation of structure \& structural evolution \ldots
 
  \underline{Augsburg}
  \begin{itemize}
-  \item Prof. B. Stritzker (accomodation at EP \RM{4})
-  \item Ralf Utermann (EDV)
+  \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}
 
- \underline{Stuttgart}
+\vspace{ 0.2cm}
+
 \begin{center}
 \framebox{
-\bf Thank you for your attention / invitation!
+\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}
 
-\fi