Design:
This source produces a very clean flux of silicon by direct current heating of a pure silicon block.
The conveniently shaped silicon block is connected to two water-cooled high current feedthroughs.
The silicon temperature determines the evaporation rate.
The complete assembly has a small thermal mass in order to permit rapid changes of the silicon temperature and,
thereby, the Si flux. Multiple doping levels can be achieved during the same layer growth.
Results:
Several A/mn of growth rate can be used. Typical total Si film thickness is about 5 to 8 µm
at 1A/mn growth rate per Silicon charge.
When used for B doping of silicon, doping densities of up to about 2 x 1019 /cm3 have been achieved
(about 4 x 1019 /cm3 for P doping).
System installation:
The cell uses a DN40CF flange ( 2.3/4’’) and can be installed on any of the major commercial MBE system ports.
When used on an MBE system with no cell LN2 or water surrounding panel
(the case of most VG systems) a water cooling circuit can be integrated on the source flange ( DN63CF – 4.5’’).
