From: hackbard Date: Fri, 11 Jun 2010 17:51:25 +0000 (+0200) Subject: sec checkin X-Git-Url: https://hackdaworld.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6923081bcd4d77d0516bce5fb8ab29bd5ec467fd;p=lectures%2Flatex.git sec checkin --- diff --git a/posic/talks/seminar_2010.tex b/posic/talks/seminar_2010.tex index fd742bb..9743c73 100644 --- a/posic/talks/seminar_2010.tex +++ b/posic/talks/seminar_2010.tex @@ -172,14 +172,14 @@ } \begin{itemize} - \item Fabrication of silicon carbide - \item Precipitation model + \item Fabrication of silicon carbide and different polytypes + \item Precipitation model of 3C-SiC in Si \item Utilized simulation techniques \begin{itemize} \item Molecular dynamics (MD) simulations \item Density functional theory (DFT) calculations \end{itemize} - \item Point defects in silicon + \item C and Si self-interstitial point defects in silicon \item Precipitation simulations \item Summary / Conclusion / Outlook \end{itemize} @@ -191,47 +191,94 @@ \begin{slide} {\large\bf - Motivation + Polytypes of SiC } + + \vspace{4cm} + + \small + +\begin{tabular}{l | c c c c c c} +\hline + & 3C-SiC & 4H-SiC & 6H-SiC & Si & GaN & Diamond\\ +\hline +Hardness [Mohs] & 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] & & & & & & \\ +Saturation drift velocity [] & & & & & & \\ +Electron mobility [] & & & & & & \\ +Hole mobility [] & & & & & & \\ +Thermal conductivity [] & & & & & & \\ +\hline +\end{tabular} + +\begin{picture}(0,0)(-160,-155) + \includegraphics[width=7cm]{polytypes.eps} +\end{picture} + +\end{slide} + +\begin{slide} + + {\large\bf + Fabrication of silicon carbide + } + + \small \vspace{4pt} SiC - \emph{Born from the stars, perfected on earth.} - + \vspace{4pt} - Herstellung d"unner SiC-Filme: + Conventional thin film SiC growth: \begin{itemize} - \item modifizierter Lely-Prozess + \item \underline{Sublimation growth using the modified Lely method} \begin{itemize} - \item Impfkristall mit $T=2200 \, ^{\circ} \text{C}$ - \item umgeben von polykristallinen SiC mit - $T=2400 \, ^{\circ} \text{C}$ + \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 CVD Homoepitaxie + \item \underline{Homoepitaxial growth using CVD} \begin{itemize} - \item 'step controlled epitaxy' auf 6H-SiC-Substrat - \item C$_3$H$_8$/SiH$_4$/H$_2$ bei $1500 \, ^{\circ} \text{C}$ - \item Winkel $\rightarrow$ 3C/6H/4H-SiC - \item hohe Qualit"at aber limitiert durch\\ - Substratgr"o"se + \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 + \item High quality but limited in size of substrates \end{itemize} - \item CVD/MBE Heteroepitaxie von 3C-SiC auf Si + \item \underline{Heteroepitaxial growth of 3C-SiC on Si using CVD/MBE} \begin{itemize} - \item 2 Schritte: Karbonisierung und Wachstum + \item Two steps: carbonization and growth \item $T=650-1050 \, ^{\circ} \text{C}$ - \item Qualit"at/Gr"o"se noch nicht ausreichend + \item Quality and size not yet sufficient \end{itemize} \end{itemize} - \begin{picture}(0,0)(-245,-50) - \includegraphics[width=5cm]{6h-sic_3c-sic.eps} + \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)(-240,-35) + \begin{picture}(0,0)(-333,-175) \begin{minipage}{5cm} - {\scriptsize - NASA: 6H-SiC LED und 3C-SiC LED\\[-6pt] - nebeneinander auf 6H-SiC-Substrat + {\tiny + 1. Lid\\[-7pt] + 2. Heating\\[-7pt] + 3. Source\\[-7pt] + 4. Crucible\\[-7pt] + 5. Insulation\\[-7pt] + 6. Seed crystal } \end{minipage} \end{picture}