Flux distribution from a cylindrical crucible

3D false-color landscape plot of a simulated flux distribution for a cylindrical crucible that is 2/3 full

2/3 full

3D false-color landscape plot of a simulated flux distribution for a cylindrical crucible that is 1/3 full

1/3 full

3D false-color landscape plot of a simulated flux distribution for a cylindrical crucible that is almost empty

almost empty

The images show the flux distribution of a narrow cylindrical crucible about ten times the length of its inner diameter. The crucible axis is tilted around 20° from the normal to the right.

The distribution is tilted, but planar, in the central ellipse and drops off rapidly outside this region. The main result is the dramatic focusing effect of a long crucible: a much larger fraction of the source material is deposited into the central region for low filling levels of the crucible. This effect counteracts the 1/r² flux reduction with melt distance from the substrate and allows efficient deposition with large working distances.