From: hackbard Date: Thu, 20 Jan 2011 17:05:06 +0000 (+0100) Subject: basically finished sic on si hetero... X-Git-Url: https://hackdaworld.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b3a906c2a0daba387d3a43fce271357e8c466552;p=lectures%2Flatex.git basically finished sic on si hetero... --- diff --git a/posic/thesis/sic.tex b/posic/thesis/sic.tex index 354f9f5..1e6d91c 100644 --- a/posic/thesis/sic.tex +++ b/posic/thesis/sic.tex @@ -170,10 +170,12 @@ Low defect densities in the buffer layer are a prerequisite for obtaining good q Next to surface morphology defects such as pits and islands, the main defects in 3C-SiC heteroepitaxial layers are twins, stacking faults (SF) and antiphase boundaries (APB) \cite{shibahara86,pirouz87}. APB defects, which constitute the primary residual defects in thick layers, are formed near surface terraces that differ in a single-atom-height step resulting in domains of SiC separated by a boundary, which consists of either Si-Si or C-C bonds due to missing or disturbed sublattice information \cite{desjardins96,kitabatake97}. However, the number of such defects can be reduced by off-axis growth on a Si \hkl(0 0 1) substrate miscut towards \hkl[1 1 0] by \unit[2]{$^{\circ}$}-\unit[4]{$^{\circ}$} \cite{shibahara86,powell87_2}. +This results in the thermodynamically favored growth of a single phase due to the uni-directional contraction of Si-C-Si bond chains perpendicular to the terrace steps edges during carbonization and the fast growth parallel to the terrace edges during growth under Si rich conditions \cite{kitabatake97}. +By MBE \cite{}, lower process temperatures than these typically employed in CVD have been realized, which is essential for limiting thermal stresses and to avoid resulting substrate bending, a key issue in obtaining large area 3C-SiC surfaces. +In summary, the almost universal use of Si has allowed significant progress in the understanding of heteroepitaxial growth of SiC on Si. +However, mismatches in the thermal expansion coefficient and the lattice parameter cause a considerably high concentration of various defects, which is responsible for structural and electrical qualities that are not not yet statisfactory. -resulting in carb and growth \cite{kitabatake97} ... - -lower temps ... to limit thermal stress due to differing expansion coefficients ... +SiC on SiC epitaxy ... \section{Ion beam synthesis of cubic silicon carbide}