Computer simulation is conducted to study the effects of ampoule rotation o
n the flows and the dopant segregation in vertical Bridgman (VB) crystal gr
owth. A benchmark problem for the growth of gallium-doped germanium in a gr
aphite ampoule is used as an example. Both pseudo-steady state and fully tr
ansient calculations are conducted. It is found that the convection and dop
ant segregation can be affected significantly by ampoule rotation, and the
effect is similar to that by an axial magnetic field. Ampoule rotation decr
eases the intensity of convection and stretches the flow cell axially. As a
result, both radial and axial segregations are affected. When the convecti
on is weak, the flow can be suppressed almost completely by moderate ampoul
e rotation and the dopant segregation becomes diffusion-controlled For stro
nger convection, the elongated flow cell by ampoule rotation may bring dopa
nt mixing into the bulk melt reducing axial segregation at the early stage
of the growth. However, if the cellular flow cannot be suppressed completel
y, ampoule rotation may induce larger radial segregation due to poor mixing
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