From: hackbard Date: Tue, 20 Oct 2009 15:38:46 +0000 (+0200) Subject: suppression of ted X-Git-Url: https://hackdaworld.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8b6d76bc32147cf227b5301f5f3dbafbe1e310df;p=lectures%2Flatex.git suppression of ted --- diff --git a/posic/thesis/intro.tex b/posic/thesis/intro.tex index 9cf3c41..68ae4d3 100644 --- a/posic/thesis/intro.tex +++ b/posic/thesis/intro.tex @@ -9,19 +9,28 @@ The realization of silicon carbide based applications demands for reasonable siz Despite the tremendous progress achieved in the fabrication of high purity SiC employing techniques like the modified Lely process for bulk crystal growth \cite{tairov78,tsvetkov98} or chemical vapour deposition (CVD) and molecular beam epitaxy (MBE) for homo- and heteroepitaxial growth \cite{kimoto93,powell90,fissel95}, available wafer dimensions and crystal qualities are not yet considered sufficient enough. Another promising alternative to fabricate SiC is ion beam synthesis (IBS). -High-dose carbon implantation into silicon with subsequent annealing results in the formation of buried epitaxial SiC layers in topotactic relationship with the silicon matrix \cite{borders71,reeson87}. -A two-temperature implantation technique was proposed to achieve single crytalline SiC layers and a sharp SiC/Si interface \cite{lindner99,lindner01,lindner02}. -Hier Ueberleitung rein ... -To observe the nucleation of SiC nanocrystals in crystalline silicon (c-Si) elevated temperatures and stoichiometric doses exceeding the solubility limit of carbon in silicon \cite{scace59} are required. +High-dose carbon implantation at elevated temperatures into silicon with subsequent annealing results in the formation of buried epitaxial SiC layers \cite{borders71,reeson87}. +A two-temperature implantation technique was proposed to achieve single crytalline SiC layers and a sharp SiC/Si interface \cite{lindner99,lindner99_2,lindner01,lindner02}. -Therefore the understanding of carbon, as an isovalent impurity in silicon is of fundamental interest... +Although high-quality SiC can be achieved by means of IBS the precipitation mechanism is not yet fully understood. +High resolution transmisson electron microscopy (HRTEM) studies indicate the formation of C-Si interstitial complexes sharing conventional silicon lattice sites (C-Si dumbbells) during the implantation of carbon in silicon. +These C-Si dumbbells agglomerate and once a critical radius is reached, the topotactic transformation into a SiC precipitate occurs \cite{werner97,lindner01}. + +A better understanding of the supposed SiC conversion mechanism and related carbon-mediated effects in silicon will enable significant technological progress in SiC thin film formation on the one hand and likewise offer perspectives for processes which rely upon prevention of precipitation events for improved silicon based devices on the other hand. +Implanted carbon is known to suppress transient enhanced diffusion (TED) of dopant species like boron or phosphorus in the annealing step \cite{cowner96} which can be exploited to create shallow p-n junctions in submicron technologies. +Si self-interstitials (Si$_{\text{i}}$), known as the transport vehicles for dopants \cite{fahey89,stolk95}, get trapped by reacting with the carbon atoms. +Furthermore carbon insertion can be used to taylor the electronic properties of ... + + +Strained silicon to achieve higher charge carrier velocities ... \\ -Control of dopant diffusion in silicon device manufacturing / transient enhanced diffusion (TED) ... + +Therefore the understanding of carbon, as an isovalent impurity in silicon is of fundamental interest... \\ -Strained silicon to achieve higher charge carrier velocities ... +Computer simulations ... \\