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Our
MBE machine consists of three vacuum chambers: the loading chamber, the
buffer chamber and the growth chamber. The loading chamber and the buffer
chamber are pumped by turbomolecular pumps. The
growth chamber is equipped with an ion pump, a turbo-molecular pump and a
titanium sublimation pump. Additionally the chamber contains cooling shields
(liquid nitrogen). The typical working pressure in the growth chamber is in
the range of 2 x 10-9mbars.
The growth chamber is equipped with three electron beam evaporation sources
which we use for the evaporation of silicon, germanium and other materials
and with up to four thermal evaporation cells which are mainly used as doping
sources. For our investigations we use materials like aluminium,
antimony and boron.
Furthermore the growth chamber contains a manipulator for 5 inch wafers, a
RHEED system, 2 quadrupole mass spectrometers and 2
quartz monitors.
The buffer chamber is equipped with a transport system which can hold a cassette. In this
cassette we can store up to eight wafers under ultra high vacuum conditions.
Via a transfer rod the wafers can be moved into the growth chamber.
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