From: hackbard Date: Tue, 26 Apr 2011 15:05:13 +0000 (+0200) Subject: some stuff on c in si X-Git-Url: https://hackdaworld.org/gitweb/?a=commitdiff_plain;h=bbe0e9b171831786e4df21dd3a37abad30f331bb;p=lectures%2Flatex.git some stuff on c in si --- diff --git a/bibdb/bibdb.bib b/bibdb/bibdb.bib index 810cb9b..a4eb408 100644 --- a/bibdb/bibdb.bib +++ b/bibdb/bibdb.bib @@ -2355,7 +2355,7 @@ Netherlands", title = "Boron implantations in silicon: {A} comparison of charge carrier and boron concentration profiles", - journal = "Applied Physics A: Materials Science & + journal = "Applied Physics A: Materials Science \& Processing", publisher = "Springer Berlin / Heidelberg", ISSN = "0947-8396", diff --git a/posic/thesis/sic.tex b/posic/thesis/sic.tex index 19ad798..b161271 100644 --- a/posic/thesis/sic.tex +++ b/posic/thesis/sic.tex @@ -303,6 +303,7 @@ Substitutional C and interstitial Si react into a C-Si complex forming a dumbbel This structure, the so called C-Si \hkl<1 0 0> dumbbell structure, was initially suspected by local vibrational mode absorption \cite{bean70} and finally verified by electron paramegnetic resonance \cite{watkins76} studies on irradiated Si substrates at low temperatures. Measuring the annealing rate of the defect as a function of temperature reveals barriers for migration ranging from \unit[0.73]{eV} \cite{song90} to \unit[0.87]{eV} \cite{tipping87}, which is highly mobile compared to substitutional C. % diffusion pathway? +% expansion of the lattice (positive strain) %\subsection{Agglomeration phenomena} % c-si agglomerattion as an alternative to sic precipitation (due to strain) @@ -313,16 +314,25 @@ Measuring the annealing rate of the defect as a function of temperature reveals The predominant diffusion mechanism of most dopants in Si based on native self-interstitials \cite{fahey89} has a large impact on the diffusion behavior of dopants that have been implanted in Si. The excess population of Si self-interstitials created by low-energy implantations of dopants for shallow junction formation in submicron technologies may enhance the diffusion of the respective dopant during annealing by more than one order of magnitude compared to normal diffusion. This kind of diffusion, labeled transient enhanced diffusion (TED), which is driven by the presence of non-equilibrium concentrations of point defects, was first discovered for implantations of boron in Si \cite{hofker74} and is well understood today \cite{michel87,cowern90,stolk95,stolk97}. -The TED of B was found to be inhibited in the presence of a sufficient amount of incorporated C \cite{covern96}. +The TED of B was found to be inhibited in the presence of a sufficient amount of incorporated C \cite{cowern96}. This is due to the reduction of the excess Si self-interstitials with substitutional C atoms forming the C-Si interstitial complex \cite{stolk97,zhu98}. Therefore, incorporation of C provides a promising method for suppressing TED enabling an improved shallow junction formation in future Si devices. +% in general: high c diffusion in areas of high damage, low diffusion for substitutional or even sic prec + \subsection{Strained silicon and silicon heterostructures} -% -> skorupa 3.2: c sub vs sic prec -% -> my own links: strane etc ... -% -> skorupa 3.5: heterostructures +% lattice location of implanted carbon +Radiation damage introduced during implantation and a high concentration of the implanted species, which results in the reduction of the topological constraint of the host lattice imposed on the implanted species, can affect the manner of impurity incorporation. +The probability of finding C, which will be most stable at sites for which the number of neighbors equals the natural valence, i.e. substitutionally on a regular Si site of a perfect lattice, is, thus, reduced at substitutional lattice sites and likewise increased to be found as an interstitial. +Depending on the way C is incorporated and whether precipitation occurs or not the volume is either reduced in the case of substitutionally incorporated C or expanded in the case of C interstitial formation \cite{goesele85}. +There are, however, ... +In implanted Si the location of C is to a great deal incorporated as an interstitial atom due to a reduced topological contraint. +Other methods exist to realize only substitutional C. + +% -> my own links: strane etc ... +% -> skorupa 3.5: heterostructures \section{Assumed cubic silicon carbide conversion mechanisms} \label{section:assumed_prec} @@ -334,6 +344,8 @@ Although tremendous progress has been achieved in the above-mentioned growth met ... \cite{lindner99_2} ... +% -> skorupa 3.2: c sub vs sic prec + on surface ... md contraction along 110 ... kitabatake ... and ref in lindner ... rheed from si to sic ... in ibs ... lindner and skorupa ...