CONVECTION DURING THE VERTICAL BRIDGMAN GROWTH OF HG1-XCDXTE

Two different structures, obtained with specific growth parameters, in Hg(1-xC)d(x)Te single crystals synthesized by the vertical Bridgman t echnique, are shown. A structure (small vertical line-shaped defects) located in the central part of the charge along the growth axis can be ascribed to convection induced by melt-solid interface curvature. The other structure, obtained in the first-to-freeze region of the ingot, when the temperature of the cold zone of the furnace is constant and a few degrees lower than the solidification one, can be ascribed to th e convection rolls frozen in the solid matrix. (C) 1998 Chapman & Hall .