A NOVEL TECHNIQUE FOR CZOCHRALSKI GROWTH OF GASB SINGLE-CRYSTALS

A novel upper-lower crucible technique for synthesis and growth of GaSb crystals from scum-free melt has been developed. The key element of the technique is a special design acting as a sluice gate in the upper crucible to trap the scum on the melt surface after GaSb melt synthesis and homogenization. The remarkable feature of this method is that only a one-step growth cycle is needed for growth from the scum-free melt in pure H-2 ambient instead of the conventional two-step growth cycle. Te-doped and undoped, [100] and [111] ''device quality'' GaSb single crystals with diameter 5 cm and a mass of 600-1000 g have been grown by this technique with a relatively high yield. The generation of twinning during crystal growth has been briefly described.