Silicon carbide (SiC) has a number of remarkable physical and chemical properties that make it a promising new material in various fields of applications.
The high electron mobility and saturation drift velocity as well as the high band gap and breakdown field in conjunction with its unique thermal stability and conductivity unveil SiC as the ideal candidate for high-power, high-frequency and high-temperature electronic and optoelectronic devices exceeding conventional silicon based solutions \cite{wesch96,morkoc94,casady96,capano97,pensl93}.
-Due to the large Si--C bonding energy SiC is a hard and chemical inert material suitable for applications under extreme conditions and capable for microelectromechanical systems (MEMS), both as structural material and as a coating layer \cite{sarro00,park98}.
+Due to the large Si--C bonding energy SiC is a hard and chemical inert material suitable for applications under extreme conditions and capable for \aclp{MEMS} (\acs{MEMS}), both as structural material and as a coating layer \cite{sarro00,park98}.
Its radiation hardness allows the operation as a first wall material in nuclear reactors \cite{giancarli98} and as electronic devices in space \cite{capano97}.
The realization of silicon carbide based applications demands for reasonable sized wafers of high crystalline quality.
Especially substrates of the 3C polytype promise good quality, single crystalline GaN films~\cite{takeuchi91,yamamoto04,ito04}.
The focus of SiC based applications, however, is in the area of solid state electronics experiencing revolutionary performance improvements enabled by its capabilities.
-These devices include ultraviolet (UV) detectors, high power radio frequency (RF) amplifiers, rectifiers and switching transistors as well as MEMS applications.
+These devices include ultraviolet (UV) detectors, high power radio frequency (RF) amplifiers, rectifiers and switching transistors as well as \ac{MEMS} applications.
For UV dtectors the wide band gap is useful for realizing low photodiode dark currents as well as sensors that are blind to undesired near-infrared wavelenghts produced by heat and solar radiation.
These photodiodes serve as excellent sensors applicable in the monitoring and control of turbine engine combustion.
The low dark currents enable the use in X-ray, heavy ion and neutron detection in nuclear reactor monitoring and enhanced scientific studies of high-energy particle collisions as well as cosmic radiation.
The high breakdown field of SiC compared to Si allows the blocking voltage region of a device to be designed roughly 10 times thinner and 10 times heavier doped, resulting in a decrease of the blocking region resistance by a factor of 100 and a much faster switching behavior.
Thus, rectifier diodes and switching transistors with higher switching frequencies and much greater efficiencies can be realized and exploited in highly efficient power converters.
Therefor, SiC constitutes a promising candidate to become the key technology towards an extensive development and use of regenerative energies and elctromobility.
-Beside the mentioned electrical capabilities the mechanical stability, which is almost as hard as diamond, and chemical inertness almost suggest SiC to be used in MEMS designs.
+Beside the mentioned electrical capabilities the mechanical stability, which is almost as hard as diamond, and chemical inertness almost suggest SiC to be used in \ac{MEMS} designs.
Among the different polytypes of SiC, the cubic phase shows a high electron mobility and the highest break down field as well as saturation drift velocity.
In contrast to its hexagonal counterparts 3C-SiC exhibits isotropic mechanical and electronic properties.
To realize single monolayer growth precise control of the gas supply to form the $(2\times 1)$ structure is required.
However, accurate layer-by-layer growth is achieved under certain conditions, which facilitate the spontaneous desorption of an additional layer of one atom species by supply of the other species \cite{hara93}.
Homoepitaxial growth of the 6H polytype has been realized on off-oriented substrates utilizing simultaneous supply of the source gases \cite{tanaka94}.
-Depending on the gas flow ratio either island formation or step flow growth occurs, which is explained by a model including aspects of enhanced surface mobilities of adatoms on a reconstructed surface.
-{\color{red} Read, understand and mabye add a bit more.}
+Depending on the gas flow ratio either 3C island formation or step flow growth of the 6H polytype occurs, which is explained by a model including aspects of enhanced surface mobilities of adatoms on a $(3\times 3)$ reconstructed surface.
Problem of gas source ... strong adsorption and incorporation of atomic decomposited hydrogen of the gas phase reactants at low temperatures.
Growth rate lower than desorption rate of hydrogen ...
To summarize ... remaining obstacles are ... APB in 3C ... and micropipes in hexagonal SiC?
-\section{Ion beam synthesis of cubic silicon carbide}
+\subsection{Ion beam synthesis of cubic silicon carbide}
\section{Substoichiometric concentrations of carbon in crystalline silicon}
\pdfoutput=0
-%\documentclass[twoside,a4paper,11pt]{book}
-\documentclass[twoside,a4paper,11pt,draft]{book}
+\documentclass[twoside,a4paper,11pt]{book}
+%\documentclass[twoside,a4paper,11pt,draft]{book}
\usepackage[activate]{pdfcprot}
\usepackage{verbatim}
\usepackage{a4}
\usepackage{slashbox}
+% acronyms
+\usepackage{acronym}
+\acrodef{ALE}{atomic layer epitaxy}
+\acrodef{APB}{anti phase boundary}
+\acrodef{CVD}{chemical vapor deposition}
+\acrodef{HDTV}{high definition television}
+\acrodef{IBS}{ion beam synthesis}
+\acrodef{LED}{light emitting diode}
+\acrodef{MBE}{molecular beam epitaxy}
+\acrodef{MEMS}{microelectromechanical system}
+\acrodef{PVT}{physical vapor transport}
+\acrodef{RF}{radio frequency}
+
+
+% units
+\usepackage{units}
+
% (re)new commands
\newcommand{\printimg}[5]{%
\begin{figure}[#1]%
\mainmatter{}
\include{intro}
+% reset all acronyms
+\acresetall
\include{sic}
\include{basics}
%\include{exp_findings}
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