23-06-2012, 02:26 PM
EPITAXY
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INTRODUCTION
Greek words - epi meaning "upon" and taxis meaning "ordered“.
Thin crystalline layer on a crystalline substrate.
Substrate wafer acts as a seed crystal.
Mostly used techniques are :-
chemical vapor deposition (CVD) .
molecular beam epitaxy (MBE).
Homoepitaxy.
Heteroepitaxy.
THEORY
Direct physical transport of the material to be grown.
Silicon and GaAs – MBE.
Gallium and arsenic are used as source materials for GaAs.
Materials are available in "seven nines" (99.99999%)