more lindner stuff, finished soon, hopefully!

diff --git a/bibdb/bibdb.bib b/bibdb/bibdb.bib
index b2b9c19..c55a0e1 100644 (file)
--- a/bibdb/bibdb.bib
+++ b/bibdb/bibdb.bib
@@ -1226,6 +1226,58 @@
   notes =        "first time ibs at moderate temperatures",
 }
 
   notes =        "first time ibs at moderate temperatures",
 }
 

+@Article{lindner96,
+  title =        "Formation of buried epitaxial silicon carbide layers
+                 in silicon by ion beam synthesis",
+  journal =      "Materials Chemistry and Physics",
+  volume =       "46",
+  number =       "2-3",
+  pages =        "147--155",
+  year =         "1996",
+  note =         "",
+  ISSN =         "0254-0584",
+  doi =          "DOI: 10.1016/S0254-0584(97)80008-9",
+  URL =          "http://www.sciencedirect.com/science/article/B6TX4-3VSGY9S-8/2/f001f23c0b3bc0fc3fc683616588fbc7",
+  author =       "J. K. N. Lindner and K. Volz and U. Preckwinkel and B.
+                 Götz and A. Frohnwieser and B. Rauschenbach and B.
+                 Stritzker",
+  notes =        "dose window",
+}
+
+@Article{calcagno96,
+  title =        "Carbon clustering in Si[sub 1-x]{C}[sub x] formed by
+                 ion implantation",
+  journal =      "Nuclear Instruments and Methods in Physics Research
+                 Section B: Beam Interactions with Materials and Atoms",
+  volume =       "120",
+  number =       "1-4",
+  pages =        "121--124",
+  year =         "1996",
+  note =         "Proceedings of the E-MRS '96 Spring Meeting Symp. I on
+                 New Trends in Ion Beam Processing of Materials",
+  ISSN =         "0168-583X",
+  doi =          "DOI: 10.1016/S0168-583X(96)00492-2",
+  URL =          "http://www.sciencedirect.com/science/article/B6TJN-3VSHB0W-1S/2/164b9f4f972a02f44b341b0de28bba1d",
+  author =       "L. Calcagno and G. Compagnini and G. Foti and M. G.
+                 Grimaldi and P. Musumeci",
+  notes =        "dose window, graphitic bonds",
+}
+
+@Article{lindner98,
+  title =        "Mechanisms of Si{C} Formation in the Ion Beam
+                 Synthesis of 3{C}-Si{C} Layers in Silicon",
+  journal =      "Materials Science Forum",
+  volume =       "264-268",
+  pages =        "215--218",
+  year =         "1998",
+  note =         "",
+  doi =          "10.4028/www.scientific.net/MSF.264-268.215",
+  URL =          "http://www.scientific.net/MSF.264-268.215",
+  author =       "J. K. N. Lindner and W. Reiber and B. Stritzker",
+  notes =        "intermediate temperature for sharp interface + good
+                 crystallinity",
+}
+

 @Article{lindner99,
   title =        "Controlling the density distribution of Si{C}
                  nanocrystals for the ion beam synthesis of buried Si{C}
 @Article{lindner99,
   title =        "Controlling the density distribution of Si{C}
                  nanocrystals for the ion beam synthesis of buried Si{C}

diff --git a/posic/thesis/sic.tex b/posic/thesis/sic.tex
index 7228cbe..256e7db 100644 (file)
--- a/posic/thesis/sic.tex
+++ b/posic/thesis/sic.tex
@@ -243,13 +243,13 @@ The authors assumed that due to the auxiliary heating rather than ion beam heati
 Even better qualities by direct synthesis were obtained for implantations at \unit[950]{$^{\circ}$C} \cite{nejim95}.
 Since no amorphous or polycrystalline regions have been identified, twinning is considered to constitute the main limiting factor in the \ac{IBS} of SiC.
 
 Even better qualities by direct synthesis were obtained for implantations at \unit[950]{$^{\circ}$C} \cite{nejim95}.
 Since no amorphous or polycrystalline regions have been identified, twinning is considered to constitute the main limiting factor in the \ac{IBS} of SiC.
 

-Further studies revealed the possibility to form buried layers of SiC by IBS at moderate substrate and anneal temperatures \cite{lindner95}.
+Further studies revealed the possibility to form buried layers of SiC by IBS at moderate substrate and anneal temperatures \cite{lindner95,lindner96}.

 Different doses of C ions with an energy of \unit[180]{keV} were implanted at \unit[330-440]{$^{\circ}$C} and annealed at \unit[1200]{$^{\circ}$C} or \unit[1250]{$^{\circ}$C} for \unit[5-10]{h}.
 For a critical dose, which was found to depend on the Si substrate orientation,  the formation of a stoichiometric buried layer of SiC exhibiting a well-defined interface to the Si host matrix was observed.
 In case of overstoichiometric C concentrations the excess C is not redistributed.
 Different doses of C ions with an energy of \unit[180]{keV} were implanted at \unit[330-440]{$^{\circ}$C} and annealed at \unit[1200]{$^{\circ}$C} or \unit[1250]{$^{\circ}$C} for \unit[5-10]{h}.
 For a critical dose, which was found to depend on the Si substrate orientation,  the formation of a stoichiometric buried layer of SiC exhibiting a well-defined interface to the Si host matrix was observed.
 In case of overstoichiometric C concentrations the excess C is not redistributed.

-These investigations demonstrate the presence of an upper dose limit, which corresponds to a \unit[50]{at.\%} C concentration at the implantation peak, for the thermally induced redistribution of the C atoms from a Gaussian to a box-shaped depth profile upon annealing.
-For higher concentrations the formation of strong C-C bonds is expected.
-Increased temperatures are necessary for the dissociation of these C clusters.
+These investigations demonstrate the presence of an upper dose limit, which corresponds to a \unit[53]{at.\%} C concentration at the implantation peak, for the thermally induced redistribution of the C atoms from a Gaussian to a box-shaped depth profile upon annealing.
+This is explained by the formation of strong graphitic C-C bonds for higher C concentrations \cite{calcagno96}.
+Increased temperatures exceeding the Si melting point are expected to be necessary for the dissociation of these C clusters.

 Furthermore, higher implantation energies were found to result in layers of variable composition exhibiting randomly distributed SiC precipitates.
 In another study \cite{serre95} high dose C implantations were performed at room temperature and \unit[500]{$^{\circ}$C} respectively.
 Implantations at room temperature lead to the formation of a buried amorphous carbide layer in addition to a thin C-rich film at the surface, which is attributed to the migration of C atoms towards the surface.
 Furthermore, higher implantation energies were found to result in layers of variable composition exhibiting randomly distributed SiC precipitates.
 In another study \cite{serre95} high dose C implantations were performed at room temperature and \unit[500]{$^{\circ}$C} respectively.
 Implantations at room temperature lead to the formation of a buried amorphous carbide layer in addition to a thin C-rich film at the surface, which is attributed to the migration of C atoms towards the surface.


@@ -257,7 +257,19 @@ In contrast, implantations at elevated temperatures result in the exclusive form
 Annealing at temperatures up to \unit[1150]{$^{\circ}$C} does not alter the C profile.
 Instead defect annihilation is observed and the C-rich surface layer of the room temperature implant turns into a layer consisting of SiC precipitates, which, however, are not aligned with the Si matrix indicating a mechanism different to the one of the direct formation for the high-temperature implantation.
 
 Annealing at temperatures up to \unit[1150]{$^{\circ}$C} does not alter the C profile.
 Instead defect annihilation is observed and the C-rich surface layer of the room temperature implant turns into a layer consisting of SiC precipitates, which, however, are not aligned with the Si matrix indicating a mechanism different to the one of the direct formation for the high-temperature implantation.
 

-..  lindner limit in dose -> 1250
+Based on these findings, a recipe was developed to form buried layers of single-crystalline SiC featuring an improved interface and crystallinity \cite{lindner99,lindner01,lindner02}.
+Therefore, the dose must not exceed the stoichiometry dose, i.e. the dose corresponding to \unit[50]{at.\%} C concentration at the implantation peak.
+Otherwise clusters of C are formed, which cannot be dissolved during post-implantation annealing at moderate temperatures below the Si melting point \cite{lindner96,calcagno96}.
+Annealing should be performed for \unit[5-10]{h} at \unit[1250]{$^{\circ}$C} to enable the redistribution from the as-implanted Gaussian into a box-like C depth profile \cite{lindner95}.
+The implantation temperature constitutes the most critical parameter, which is responsible for the structure after implantation and, thus, the starting point for subsequent annealing steps.
+
+
+\cite{lindner98} sharp interface and good crystallinity
+
+improved two-temperature implantation \cite{lindner99}.
+
+By understanding these basic processes
+... lindner limit in dose -> 1250

 ... two temp implantation ... sharp interface
 By understanding some basic processes (32-36), \ac{IBS} nowadays has become a promising method to form thin SiC layers of high quality exclusively of the 3C polytype embedded in and epitactically aligned to the Si host featuring a sharp interface \cite{lindner99,lindner01,lindner02}.
 
 ... two temp implantation ... sharp interface
 By understanding some basic processes (32-36), \ac{IBS} nowadays has become a promising method to form thin SiC layers of high quality exclusively of the 3C polytype embedded in and epitactically aligned to the Si host featuring a sharp interface \cite{lindner99,lindner01,lindner02}.
 


@@ -268,6 +280,8 @@ diffusion mechanism, lattice distortion, hmm ... extra section needed?
 \section{Assumed cubic silicon carbide conversion mechanisms}
 \label{section:assumed_prec}
 
 \section{Assumed cubic silicon carbide conversion mechanisms}
 \label{section:assumed_prec}
 

+... \cite{lindner99_2} ...
+

 on surface ... md contraction along 110 ... kitabatake ... and ref in lindner ... rheed from si to sic ...
 
 in ibs ... lindner and skorupa ...
 on surface ... md contraction along 110 ... kitabatake ... and ref in lindner ... rheed from si to sic ...
 
 in ibs ... lindner and skorupa ...