X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=posic%2Ftalks%2Fseminar_2010.tex;h=19a85785ea2318bffa0163102972107455962c2b;hb=0bfdf7eadfe8ca644895e758f5ba0bab4e04dba9;hp=58369fab1c5fee4dc78b2bd011e7b56cbddb7798;hpb=f9465130d3e796c6cf3a381b62285c281704b7ab;p=lectures%2Flatex.git diff --git a/posic/talks/seminar_2010.tex b/posic/talks/seminar_2010.tex index 58369fa..19a8578 100644 --- a/posic/talks/seminar_2010.tex +++ b/posic/talks/seminar_2010.tex @@ -1,5 +1,5 @@ \pdfoutput=0 -\documentclass[landscape,semhelv]{seminar} +\documentclass[landscape,semhelv,draft]{seminar} \usepackage{verbatim} \usepackage[greek,german]{babel} @@ -71,6 +71,9 @@ % itemize level ii \renewcommand\labelitemii{{\color{gray}$\bullet$}} +% nice phi +\renewcommand{\phi}{\varphi} + % colors \newrgbcolor{si-yellow}{.6 .6 0} \newrgbcolor{hb}{0.75 0.77 0.89} @@ -342,6 +345,7 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ XTEM micrograph of single crystalline 3C-SiC in Si\hkl(1 0 0) } \end{minipage} +\framebox{ \begin{minipage}{6.3cm} \begin{center} {\color{blue} @@ -356,6 +360,7 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ \end{itemize} \end{center} \end{minipage} +} \end{slide} @@ -439,7 +444,7 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ \begin{slide} {\large\bf - Basics of molecular dynamics (MD) simulations + Molecular dynamics (MD) simulations } \vspace{12pt} @@ -465,7 +470,7 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ $\tau_{\text{P}}=100\text{ fs}$, $\beta^{-1}=100\text{ GPa}$ \end{itemize} - \item Potential: Tersoff-like bond order potential + \item Erhart/Albe potential: Tersoff-like bond order potential \vspace*{12pt} \[ E = \frac{1}{2} \sum_{i \neq j} \pot_{ij}, \quad @@ -482,33 +487,1000 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ \begin{slide} {\large\bf - Basics of density functional theory (DFT) calculations + Density functional theory (DFT) calculations } \small - Ingredients + Basic ingredients necessary for DFT + \begin{itemize} - \item Hohenberg-Kohn (HK) theorem + \item \underline{Hohenberg-Kohn theorem} - ground state density $n_0(r)$ ... + \begin{itemize} + \item ... uniquely determines the ground state potential + / wavefunctions + \item ... minimizes the systems total energy + \end{itemize} \item \underline{Born-Oppenheimer} - - $N$ moving electrons in an external potential of static nuclei\\ + - $N$ moving electrons in an external potential of static nuclei \[ H\Psi = \left[-\sum_i^N \frac{\hbar^2}{2m}\nabla_i^2 +\sum_i^N V_{\text{ext}}(r_i) +\sum_{i}{init}{insert} + \ncline[]{->}{insert}{cool} + \end{pspicture} +\end{minipage} +\begin{minipage}{5cm} + \includegraphics[width=5cm]{unit_cell_e.eps}\\ +\end{minipage} + +\begin{minipage}{9cm} + \begin{tabular}{l c c} + \hline + & size [unit cells] & \# atoms\\ +\hline +VASP & $3\times 3\times 3$ & $216\pm 1$ \\ +Erhart/Albe & $9\times 9\times 9$ & $5832\pm 1$\\ +\hline + \end{tabular} +\end{minipage} +\begin{minipage}{4cm} +{\color{red}$\bullet$} Tetrahedral\\ +{\color{green}$\bullet$} Hexagonal\\ +{\color{yellow}$\bullet$} \hkl<1 0 0> dumbbell\\ +{\color{magenta}$\bullet$} \hkl<1 1 0> dumbbell\\ +{\color{cyan}$\bullet$} Bond-centered\\ +{\color{black}$\bullet$} Vacancy / Substitutional +\end{minipage} + +\end{slide} + +\begin{slide} + + \footnotesize + +\begin{minipage}{9.5cm} + + {\large\bf + Si self-interstitial point defects in silicon\\ + } + +\begin{tabular}{l c c c c c} +\hline + $E_{\text{f}}$ [eV] & \hkl<1 1 0> DB & H & T & \hkl<1 0 0> DB & V \\ +\hline + VASP & \underline{3.39} & 3.42 & 3.77 & 4.41 & 3.63 \\ + Erhart/Albe & 4.39 & 4.48$^*$ & \underline{3.40} & 5.42 & 3.13 \\ +\hline +\end{tabular}\\[0.2cm] + +\begin{minipage}{4.7cm} +\includegraphics[width=4.7cm]{e_kin_si_hex.ps} +\end{minipage} +\begin{minipage}{4.7cm} +\begin{center} +{\tiny nearly T $\rightarrow$ T}\\ +\end{center} +\includegraphics[width=4.7cm]{nhex_tet.ps} +\end{minipage}\\ + +\underline{Hexagonal} \hspace{2pt} +\href{../video/si_self_int_hexa.avi}{$\rhd$}\\[0.1cm] +\framebox{ +\begin{minipage}{2.7cm} +$E_{\text{f}}^*=4.48\text{ eV}$\\ +\includegraphics[width=2.7cm]{si_pd_albe/hex_a.eps} +\end{minipage} +\begin{minipage}{0.4cm} +\begin{center} +$\Rightarrow$ +\end{center} +\end{minipage} +\begin{minipage}{2.7cm} +$E_{\text{f}}=3.96\text{ eV}$\\ +\includegraphics[width=2.8cm]{si_pd_albe/hex.eps} +\end{minipage} +} +\begin{minipage}{2.9cm} +\begin{flushright} +\underline{Vacancy}\\ +\includegraphics[width=3.0cm]{si_pd_albe/vac.eps} +\end{flushright} +\end{minipage} + +\end{minipage} +\begin{minipage}{3.5cm} + +\begin{flushright} +\underline{\hkl<1 1 0> dumbbell}\\ +\includegraphics[width=3.0cm]{si_pd_albe/110.eps}\\ +\underline{Tetrahedral}\\ +\includegraphics[width=3.0cm]{si_pd_albe/tet.eps}\\ +\underline{\hkl<1 0 0> dumbbell}\\ +\includegraphics[width=3.0cm]{si_pd_albe/100.eps} +\end{flushright} + +\end{minipage} + +\end{slide} + +\begin{slide} + +\footnotesize + + {\large\bf + C interstitial point defects in silicon\\[-0.1cm] + } + +\begin{tabular}{l c c c c c c} +\hline + $E_{\text{f}}$ & T & H & \hkl<1 0 0> DB & \hkl<1 1 0> DB & S & B \\ +\hline + VASP & unstable & unstable & \underline{3.72} & 4.16 & 1.95 & 4.66 \\ + Erhart/Albe MD & 6.09 & 9.05$^*$ & \underline{3.88} & 5.18 & 0.75 & 5.59$^*$ \\ +\hline +\end{tabular}\\[0.1cm] + +\framebox{ +\begin{minipage}{2.7cm} +\underline{Hexagonal} \hspace{2pt} +\href{../video/c_in_si_int_hexa.avi}{$\rhd$}\\ +$E_{\text{f}}^*=9.05\text{ eV}$\\ +\includegraphics[width=2.7cm]{c_pd_albe/hex.eps} +\end{minipage} +\begin{minipage}{0.4cm} +\begin{center} +$\Rightarrow$ +\end{center} +\end{minipage} +\begin{minipage}{2.7cm} +\underline{\hkl<1 0 0>}\\ +$E_{\text{f}}=3.88\text{ eV}$\\ +\includegraphics[width=2.7cm]{c_pd_albe/100.eps} +\end{minipage} +} +\begin{minipage}{2cm} +\hfill +\end{minipage} +\begin{minipage}{3cm} +\begin{flushright} +\underline{Tetrahedral}\\ +\includegraphics[width=3.0cm]{c_pd_albe/tet.eps} +\end{flushright} +\end{minipage} + +\framebox{ +\begin{minipage}{2.7cm} +\underline{Bond-centered}\\ +$E_{\text{f}}^*=5.59\text{ eV}$\\ +\includegraphics[width=2.7cm]{c_pd_albe/bc.eps} +\end{minipage} +\begin{minipage}{0.4cm} +\begin{center} +$\Rightarrow$ +\end{center} +\end{minipage} +\begin{minipage}{2.7cm} +\underline{\hkl<1 1 0> dumbbell}\\ +$E_{\text{f}}=5.18\text{ eV}$\\ +\includegraphics[width=2.7cm]{c_pd_albe/110.eps} +\end{minipage} +} +\begin{minipage}{2cm} +\hfill +\end{minipage} +\begin{minipage}{3cm} +\begin{flushright} +\underline{Substitutional}\\ +\includegraphics[width=3.0cm]{c_pd_albe/sub.eps} +\end{flushright} +\end{minipage} + +\end{slide} + +\begin{slide} + +\footnotesize + + {\large\bf\boldmath + C \hkl<1 0 0> dumbbell interstitial configuration\\ + } + +{\tiny +\begin{tabular}{l c c c c c c c c} +\hline + Distances [nm] & $r(1C)$ & $r(2C)$ & $r(3C)$ & $r(12)$ & $r(13)$ & $r(34)$ & $r(23)$ & $r(25)$ \\ +\hline +Erhart/Albe & 0.175 & 0.329 & 0.186 & 0.226 & 0.300 & 0.343 & 0.423 & 0.425 \\ +VASP & 0.174 & 0.341 & 0.182 & 0.229 & 0.286 & 0.347 & 0.422 & 0.417 \\ +\hline +\end{tabular}\\[0.2cm] +\begin{tabular}{l c c c c } +\hline + Angles [$^{\circ}$] & $\theta_1$ & $\theta_2$ & $\theta_3$ & $\theta_4$ \\ +\hline +Erhart/Albe & 140.2 & 109.9 & 134.4 & 112.8 \\ +VASP & 130.7 & 114.4 & 146.0 & 107.0 \\ +\hline +\end{tabular}\\[0.2cm] +\begin{tabular}{l c c c} +\hline + Displacements [nm]& $a$ & $b$ & $|a|+|b|$ \\ +\hline +Erhart/Albe & 0.084 & -0.091 & 0.175 \\ +VASP & 0.109 & -0.065 & 0.174 \\ +\hline +\end{tabular}\\[0.6cm] +} + +\begin{minipage}{3.0cm} +\begin{center} +\underline{Erhart/Albe} +\includegraphics[width=3.0cm]{c_pd_albe/100_cmp.eps} +\end{center} +\end{minipage} +\begin{minipage}{3.0cm} +\begin{center} +\underline{VASP} +\includegraphics[width=3.0cm]{c_pd_vasp/100_cmp.eps} +\end{center} +\end{minipage}\\ + +\begin{picture}(0,0)(-185,10) +\includegraphics[width=6.8cm]{100-c-si-db_cmp.eps} +\end{picture} +\begin{picture}(0,0)(-280,-150) +\includegraphics[width=3.3cm]{c_pd_vasp/eden.eps} +\end{picture} + +\begin{pspicture}(0,0)(0,0) +\psellipse[linecolor=green](5.18,5.92)(0.5,0.3) +\psellipse[linecolor=red](3.45,5.92)(1.0,0.4) +\psellipse[linecolor=blue](2.7,6.92)(0.9,0.2) +\psellipse[linecolor=blue](4.65,6.92)(0.9,0.2) +\end{pspicture} + +\end{slide} + +\begin{slide} + +\small + +\begin{minipage}{8.5cm} + + {\large\bf + Bond-centered interstitial configuration\\[-0.1cm] + } + +\begin{minipage}{3.0cm} +\includegraphics[width=2.8cm]{c_pd_vasp/bc_2333.eps}\\ +\end{minipage} +\begin{minipage}{5.2cm} +\begin{itemize} + \item Linear Si-C-Si bond + \item Si: one C \& 3 Si neighbours + \item Spin polarized calculations + \item No saddle point!\\ + Real local minimum! +\end{itemize} +\end{minipage} + +\framebox{ + \tiny + \begin{minipage}[t]{6.5cm} + \begin{minipage}[t]{1.2cm} + {\color{red}Si}\\ + {\tiny sp$^3$}\\[0.8cm] + \underline{${\color{black}\uparrow}$} + \underline{${\color{black}\uparrow}$} + \underline{${\color{black}\uparrow}$} + \underline{${\color{red}\uparrow}$}\\ + sp$^3$ + \end{minipage} + \begin{minipage}[t]{1.4cm} + \begin{center} + {\color{red}M}{\color{blue}O}\\[0.8cm] + \underline{${\color{blue}\uparrow}{\color{white}\downarrow}$}\\ + $\sigma_{\text{ab}}$\\[0.5cm] + \underline{${\color{red}\uparrow}{\color{blue}\downarrow}$}\\ + $\sigma_{\text{b}}$ + \end{center} + \end{minipage} + \begin{minipage}[t]{1.0cm} + \begin{center} + {\color{blue}C}\\ + {\tiny sp}\\[0.2cm] + \underline{${\color{white}\uparrow\uparrow}$} + \underline{${\color{white}\uparrow\uparrow}$}\\ + 2p\\[0.4cm] + \underline{${\color{blue}\uparrow}{\color{blue}\downarrow}$} + \underline{${\color{blue}\uparrow}{\color{blue}\downarrow}$}\\ + sp + \end{center} + \end{minipage} + \begin{minipage}[t]{1.4cm} + \begin{center} + {\color{blue}M}{\color{green}O}\\[0.8cm] + \underline{${\color{blue}\uparrow}{\color{white}\downarrow}$}\\ + $\sigma_{\text{ab}}$\\[0.5cm] + \underline{${\color{green}\uparrow}{\color{blue}\downarrow}$}\\ + $\sigma_{\text{b}}$ + \end{center} + \end{minipage} + \begin{minipage}[t]{1.2cm} + \begin{flushright} + {\color{green}Si}\\ + {\tiny sp$^3$}\\[0.8cm] + \underline{${\color{green}\uparrow}$} + \underline{${\color{black}\uparrow}$} + \underline{${\color{black}\uparrow}$} + \underline{${\color{black}\uparrow}$}\\ + sp$^3$ + \end{flushright} + \end{minipage} + \end{minipage} +}\\[0.1cm] + +\framebox{ +\begin{minipage}{4.5cm} +\includegraphics[width=4cm]{c_100_mig_vasp/im_spin_diff.eps} +\end{minipage} +\begin{minipage}{3.5cm} +{\color{gray}$\bullet$} Spin up\\ +{\color{green}$\bullet$} Spin down\\ +{\color{blue}$\bullet$} Resulting spin up\\ +{\color{yellow}$\bullet$} Si atoms\\ +{\color{red}$\bullet$} C atom +\end{minipage} +} + +\end{minipage} +\begin{minipage}{4.2cm} +\begin{flushright} +\includegraphics[width=4.3cm]{c_pd_vasp/bc_2333_ksl.ps}\\ +{\color{green}$\Box$} {\tiny unoccupied}\\ +{\color{red}$\bullet$} {\tiny occupied} +\end{flushright} +\end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf\boldmath + Migration of the C \hkl<1 0 0> dumbbell interstitial + } + +\scriptsize + + {\small Investigated pathways} + +\begin{minipage}{8.5cm} +\begin{minipage}{8.3cm} +\underline{\hkl<0 0 -1> $\rightarrow$ \hkl<0 0 1>}\\ +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/100_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/bc_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/100_next_2333.eps} +\end{minipage} +\end{minipage}\\ +\begin{minipage}{8.3cm} +\underline{\hkl<0 0 -1> $\rightarrow$ \hkl<0 -1 0>}\\ +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/100_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/00-1-0-10_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/0-10_2333.eps} +\end{minipage} +\end{minipage}\\ +\begin{minipage}{8.3cm} +\underline{\hkl<0 0 -1> $\rightarrow$ \hkl<0 -1 0> (in place)}\\ +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/100_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/00-1_ip0-10_2333.eps} +\end{minipage} +\begin{minipage}{0.4cm} +$\rightarrow$ +\end{minipage} +\begin{minipage}{2.4cm} +\includegraphics[width=2.4cm]{c_pd_vasp/0-10_ip_2333.eps} +\end{minipage} +\end{minipage} +\end{minipage} +\framebox{ +\begin{minipage}{4.2cm} + {\small Constrained relaxation\\ + technique (CRT) method}\\ +\includegraphics[width=4cm]{crt_orig.eps} +\begin{itemize} + \item Constrain diffusing atom + \item Static constraints +\end{itemize} +\vspace*{0.3cm} + {\small Modifications}\\ +\includegraphics[width=4cm]{crt_mod.eps} +\begin{itemize} + \item Constrain all atoms + \item Update individual\\ + constraints +\end{itemize} +\end{minipage} +} + +\end{slide} + +\begin{slide} + + {\large\bf\boldmath + Migration of the C \hkl<1 0 0> dumbbell interstitial + } + +\scriptsize + +\framebox{ +\begin{minipage}{5.9cm} +\begin{flushleft} +\includegraphics[width=5.8cm]{im_00-1_nosym_sp_fullct_thesis.ps}\\[0.45cm] +\end{flushleft} +\begin{center} +\begin{picture}(0,0)(60,0) +\includegraphics[width=1cm]{vasp_mig/00-1.eps} +\end{picture} +\begin{picture}(0,0)(-5,0) +\includegraphics[width=1cm]{vasp_mig/bc_00-1_sp.eps} +\end{picture} +\begin{picture}(0,0)(-55,0) +\includegraphics[width=1cm]{vasp_mig/bc.eps} +\end{picture} +\begin{picture}(0,0)(12.5,10) +\includegraphics[width=1cm]{110_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,0) +\includegraphics[height=0.9cm]{001_arrow.eps} +\end{picture} +\end{center} +\vspace*{0.35cm} +\end{minipage} +} +\begin{minipage}{0.3cm} +\hfill +\end{minipage} +\framebox{ +\begin{minipage}{5.9cm} +\begin{flushright} +\includegraphics[width=5.9cm]{vasp_mig/00-1_0-10_nosym_sp_fullct.ps}\\[0.5cm] +\end{flushright} +\begin{center} +\begin{picture}(0,0)(60,0) +\includegraphics[width=1cm]{vasp_mig/00-1_a.eps} +\end{picture} +\begin{picture}(0,0)(5,0) +\includegraphics[width=1cm]{vasp_mig/00-1_0-10_sp.eps} +\end{picture} +\begin{picture}(0,0)(-55,0) +\includegraphics[width=1cm]{vasp_mig/0-10.eps} +\end{picture} +\begin{picture}(0,0)(12.5,10) +\includegraphics[width=1cm]{100_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,0) +\includegraphics[height=0.9cm]{001_arrow.eps} +\end{picture} +\end{center} +\vspace*{0.3cm} +\end{minipage}\\ +} + +\vspace*{0.05cm} + +\framebox{ +\begin{minipage}{5.9cm} +\begin{flushleft} +\includegraphics[width=5.9cm]{vasp_mig/00-1_ip0-10_nosym_sp_fullct.ps}\\[0.6cm] +\end{flushleft} +\begin{center} +\begin{picture}(0,0)(60,0) +\includegraphics[width=0.9cm]{vasp_mig/00-1_b.eps} +\end{picture} +\begin{picture}(0,0)(10,0) +\includegraphics[width=0.9cm]{vasp_mig/00-1_ip0-10_sp.eps} +\end{picture} +\begin{picture}(0,0)(-60,0) +\includegraphics[width=0.9cm]{vasp_mig/0-10_b.eps} +\end{picture} +\begin{picture}(0,0)(12.5,10) +\includegraphics[width=1cm]{100_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,0) +\includegraphics[height=0.9cm]{001_arrow.eps} +\end{picture} +\end{center} +\vspace*{0.3cm} +\end{minipage} +} +\begin{minipage}{0.3cm} +\hfill +\end{minipage} +\begin{minipage}{6.5cm} +VASP results +\begin{itemize} + \item Energetically most favorable path + \begin{itemize} + \item Path 2 + \item Activation energy: $\approx$ 0.9 eV + \item Experimental values: 0.73 ... 0.87 eV + \end{itemize} + $\Rightarrow$ {\color{blue}Diffusion} path identified! + \item Reorientation (path 3) + \begin{itemize} + \item More likely composed of two consecutive steps of type 2 + \item Experimental values: 0.77 ... 0.88 eV + \end{itemize} + $\Rightarrow$ {\color{blue}Reorientation} transition identified! +\end{itemize} +\end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf\boldmath + Migration of the C \hkl<1 0 0> dumbbell interstitial + } + +\scriptsize + +\begin{minipage}{6.5cm} + +\framebox{ +\begin{minipage}{5.9cm} +\begin{flushleft} +\includegraphics[width=5.9cm]{bc_00-1.ps}\\[2.35cm] +\end{flushleft} +\begin{center} +\begin{pspicture}(0,0)(0,0) +\psframe[linecolor=red,fillstyle=none](-2.8,1.35)(3.3,2.7) +\end{pspicture} +\begin{picture}(0,0)(60,-50) +\includegraphics[width=1cm]{albe_mig/bc_00-1_red_00.eps} +\end{picture} +\begin{picture}(0,0)(5,-50) +\includegraphics[width=1cm]{albe_mig/bc_00-1_red_01.eps} +\end{picture} +\begin{picture}(0,0)(-55,-50) +\includegraphics[width=1cm]{albe_mig/bc_00-1_red_02.eps} +\end{picture} +\begin{picture}(0,0)(12.5,-40) +\includegraphics[width=1cm]{110_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,-45) +\includegraphics[height=0.9cm]{001_arrow.eps} +\end{picture}\\ +\begin{pspicture}(0,0)(0,0) +\psframe[linecolor=blue,fillstyle=none](-2.8,0)(3.3,1.6) +\end{pspicture} +\begin{picture}(0,0)(60,-15) +\includegraphics[width=0.9cm]{albe_mig/bc_00-1_01.eps} +\end{picture} +\begin{picture}(0,0)(35,-15) +\includegraphics[width=0.9cm]{albe_mig/bc_00-1_02.eps} +\end{picture} +\begin{picture}(0,0)(-5,-15) +\includegraphics[width=0.9cm]{albe_mig/bc_00-1_03.eps} +\end{picture} +\begin{picture}(0,0)(-55,-15) +\includegraphics[width=0.9cm]{albe_mig/bc_00-1_04.eps} +\end{picture} +\begin{picture}(0,0)(12.5,-5) +\includegraphics[width=1cm]{100_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,-15) +\includegraphics[height=0.9cm]{010_arrow.eps} +\end{picture} +\end{center} +\end{minipage} +}\\[0.1cm] + +\begin{minipage}{5.9cm} +Erhart/Albe results +\begin{itemize} + \item Lowest activation energy: $\approx$ 2.2 eV + \item 2.4 times higher than VASP + \item Different pathway + \item Transition minima ($\rightarrow$ \hkl<1 1 0> dumbbell) +\end{itemize} +\end{minipage} + +\end{minipage} +\begin{minipage}{6.5cm} + +\framebox{ +\begin{minipage}{5.9cm} +\begin{flushright} +\includegraphics[width=5.9cm]{00-1_0-10.ps}\\[0.75cm] +\end{flushright} +\begin{center} +\begin{pspicture}(0,0)(0,0) +\psframe[linecolor=red,fillstyle=none](-2.8,-0.25)(3.3,1.1) +\end{pspicture} +\begin{picture}(0,0)(60,-5) +\includegraphics[width=0.9cm]{albe_mig/00-1_0-10_red_00.eps} +\end{picture} +\begin{picture}(0,0)(0,-5) +\includegraphics[width=0.9cm]{albe_mig/00-1_0-10_red_min.eps} +\end{picture} +\begin{picture}(0,0)(-55,-5) +\includegraphics[width=0.9cm]{albe_mig/00-1_0-10_red_03.eps} +\end{picture} +\begin{picture}(0,0)(12.5,5) +\includegraphics[width=1cm]{100_arrow.eps} +\end{picture} +\begin{picture}(0,0)(90,0) +\includegraphics[height=0.9cm]{001_arrow.eps} +\end{picture} +\end{center} +\vspace{0.2cm} +\end{minipage} +}\\[0.2cm] + +\framebox{ +\begin{minipage}{5.9cm} +\includegraphics[width=5.9cm]{00-1_ip0-10.ps} +\end{minipage} +} + +\end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf\boldmath + 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} +\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] + +Erhart/Albe + +\begin{minipage}{6.0cm} +\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 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} +\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 C-Si \hkl<1 0 0>-type interstitials + } + +\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} + +\begin{slide} + + {\large\bf + Silicon carbide precipitation simulations + } + + \small + +\end{slide} + +\begin{slide} + + {\large\bf + Investigation of a silicon carbide precipitate in silicon + } + + \small + + + +\end{slide} \end{document}