From 0bfdf7eadfe8ca644895e758f5ba0bab4e04dba9 Mon Sep 17 00:00:00 2001 From: hackbard Date: Wed, 16 Jun 2010 01:57:59 +0200 Subject: [PATCH] finished parts of combos + todo ... --- posic/talks/seminar_2010.tex | 186 +++++++++++++++++++++++++++++++---- 1 file changed, 166 insertions(+), 20 deletions(-) diff --git a/posic/talks/seminar_2010.tex b/posic/talks/seminar_2010.tex index 2b7ef58..19a8578 100644 --- a/posic/talks/seminar_2010.tex +++ b/posic/talks/seminar_2010.tex @@ -1263,26 +1263,26 @@ Erhart/Albe results \begin{slide} {\large\bf\boldmath - Migrations involving the C \hkl<1 1 0> dumbbell interstitial\\[-0.1cm] + Migrations involving the C \hkl<1 1 0> dumbbell interstitial } \small +\vspace*{0.1cm} + VASP \begin{minipage}{6.0cm} \includegraphics[width=6cm]{vasp_mig/110_mig_vasp.ps} \end{minipage} \begin{minipage}{7cm} -\begin{itemize} - \item Alternative pathway and energies [eV]:\\ - \hkl<0 -1 0> $\stackrel{0.7}{\rightarrow}$ - \hkl<1 1 0> $\stackrel{0.95}{\rightarrow}$ - bond-centered $\stackrel{0.25}{\rightarrow}$ \hkl<0 0 -1> - \item Consists of three single transitions - \item Activation energy of second transition slightly higher - than direct transition (path 2) -\end{itemize} +\underline{Alternative pathway and energies [eV]}\\[0.1cm] +\hkl<0 -1 0> $\stackrel{0.7}{{\color{red}\longrightarrow}}$ +\hkl<1 1 0> $\stackrel{0.95}{{\color{blue}\longrightarrow}}$ +BC $\stackrel{0.25}{\longrightarrow}$ \hkl<0 0 -1>\\[0.3cm] +Composed of three single transitions\\[0.3cm] +Activation energy of second transition slightly\\ +higher than direct transition (path 2)\\[0.3cm] $\Rightarrow$ very unlikely to happen \end{minipage}\\[0.2cm] @@ -1292,28 +1292,172 @@ Erhart/Albe \includegraphics[width=6cm]{110_mig.ps} \end{minipage} \begin{minipage}{7cm} +\underline{Alternative pathway and energies [eV]}\\[0.1cm] +\hkl<0 0 -1> $\stackrel{2.2}{{\color{green}\longrightarrow}}$ +\hkl<1 1 0> $\stackrel{0.9}{{\color{red}\longrightarrow}}$ +\hkl<0 0 -1>\\[0.3cm] +Composed of two single transitions\\[0.3cm] +Compared to direct transition: (2.2 eV \& 0.5 eV)\\[0.3cm] +$\Rightarrow$ more readily constituting a probable transition +\end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf\boldmath + Combinations with a C-Si \hkl<1 0 0>-type interstitial + } + +\small + +\vspace*{0.1cm} + +Binding energy: +$ +E_{\text{b}}= +E_{\text{f}}^{\text{defect combination}}- +E_{\text{f}}^{\text{C \hkl<0 0 -1> dumbbell}}- +E_{\text{f}}^{\text{2nd defect}} +$ + +\vspace*{0.1cm} + +{\scriptsize +\begin{tabular}{l c c c c c c} +\hline + $E_{\text{b}}$ [eV] & 1 & 2 & 3 & 4 & 5 & R\\ + \hline + \hkl<0 0 -1> & {\color{red}-0.08} & -1.15 & {\color{red}-0.08} & 0.04 & -1.66 & -0.19\\ + \hkl<0 0 1> & 0.34 & 0.004 & -2.05 & 0.26 & -1.53 & -0.19\\ + \hkl<0 -1 0> & {\color{orange}-2.39} & -0.17 & {\color{green}-0.10} & {\color{blue}-0.27} & {\color{magenta}-1.88} & {\color{gray}-0.05}\\ + \hkl<0 1 0> & {\color{cyan}-2.25} & -1.90 & {\color{cyan}-2.25} & {\color{purple}-0.12} & {\color{violet}-1.38} & {\color{yellow}-0.06}\\ + \hkl<-1 0 0> & {\color{orange}-2.39} & -0.36 & {\color{cyan}-2.25} & {\color{purple}-0.12} & {\color{magenta}-1.88} & {\color{gray}-0.05}\\ + \hkl<1 0 0> & {\color{cyan}-2.25} & -2.16 & {\color{green}-0.10} & {\color{blue}-0.27} & {\color{violet}-1.38} & {\color{yellow}-0.06}\\ + \hline + C substitutional (C$_{\text{S}}$) & 0.26 & -0.51 & -0.93 & -0.15 & 0.49 & -0.05\\ + Vacancy & -5.39 ($\rightarrow$ C$_{\text{S}}$) & -0.59 & -3.14 & -0.54 & -0.50 & -0.31\\ +\hline +\end{tabular} +} + +\vspace*{0.3cm} + +\footnotesize + +\begin{minipage}[t]{3.8cm} +\underline{\hkl<1 0 0> at position 1}\\[0.1cm] +\includegraphics[width=3.5cm]{00-1dc/2-25.eps} +\end{minipage} +\begin{minipage}[t]{3.5cm} +\underline{\hkl<0 -1 0> at position 1}\\[0.1cm] +\includegraphics[width=3.2cm]{00-1dc/2-39.eps} +\end{minipage} +\begin{minipage}[t]{5.5cm} \begin{itemize} - \item Alternative pathway and energies [eV]:\\ - \hkl<0 0 -1> $\stackrel{2.2}{\rightarrow}$ - \hkl<1 1 0> $\stackrel{0.9}{\rightarrow}$ - \hkl<0 0 -1> - \item Consists of two single transitions - \item Quite compareable with the transition - passing the bond-centered configuration (0.9 eV \& 0.5 eV) + \item Restricted to VASP simulations + \item $E_{\text{b}}=0$ for isolated non-interacting defects + \item $E_{\text{b}} \rightarrow 0$ for increasing distance (R) + \item Stress compensation / increase + \item Most favorable: C clustering + \item Unfavored: antiparallel orientations + \item Indication of energetically favored\\ + agglomeration \end{itemize} -$\Rightarrow$ constitutes a probable transition \end{minipage} +\begin{picture}(0,0)(-295,-130) +\includegraphics[width=3.5cm]{comb_pos.eps} +\end{picture} + \end{slide} \begin{slide} {\large\bf\boldmath - Combinations of point defects + Combinations of C-Si \hkl<1 0 0>-type interstitials } -\scriptsize +\small + +\vspace*{0.1cm} + +Energetically most favorable combinations along \hkl<1 1 0> + +{\scriptsize +\begin{tabular}{l c c c c c c} +\hline + & 1 & 2 & 3 & 4 & 5 & 6\\ +\hline +$E_{\text{b}}$ [eV] & -2.39 & -1.88 & -0.59 & -0.31 & -0.24 & -0.21 \\ +C-C distance [\AA] & 1.4 & 4.6 & 6.5 & 8.6 & 10.5 & 10.8 \\ +Type & \hkl<-1 0 0> & \hkl<1 0 0> & \hkl<1 0 0> & \hkl<1 0 0> & \hkl<1 0 0> & \hkl<1 0 0>, \hkl<0 -1 0>\\ +\hline +\end{tabular} +} + +\vspace*{0.1cm} +\begin{minipage}{7.0cm} +\includegraphics[width=7cm,draft=false]{db_along_110_cc.ps} +\end{minipage} +\begin{minipage}{6.0cm} +\begin{itemize} + \item Interaction proportional to reciprocal cube of C-C distance + \item + \item +\end{itemize} +\end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf + Combinations of substitutional C and \hkl<1 1 0> Si self-interstitials + } + + \small + +\end{slide} + +\begin{slide} + + {\large\bf + Migration of combined defects + } + + \small + + present (describe) two starting confs, i.e. vac in c-Si + + present migration results $\rightarrow$ SiC + +\end{slide} + +\begin{slide} + + {\large\bf + Silicon carbide precipitation simulations + } + + \small + + restricted to classical MD + + explain procedure + + then there is: + + 1. temperature as in exps + + 2. exkurs: limitations of conv... + + 3. increased temp ... high and low + + 4. temperature limit + + 5. final TODO \end{slide} @@ -1335,6 +1479,8 @@ $\Rightarrow$ constitutes a probable transition \small + + \end{slide} \end{document} -- 2.20.1