Crystal growth of IV–VI semiconductors in a centrifuge

Abstract

Crystals of Ag-doped PbTe and Pb 0.83Sn 0.17Te have been grown in a Bridgman furnace placed at the extremity of the arm of a centrifuge. The melt is thus submitted to a force Ng which may be larger than the gravity force g. The surcharge N changes the convection regime in the melt. It was found that, for a well-defined value N s of the surcharge, the crystals were more perfect and the impurity profile became similar to the profile found for non-conventive conditions. N s is independent of the material and of the geometry of the liquid, but depends on the arm length of the centrifuge.