GROWTH OF CDTE MONOGRAIN POWDERS

The preparation of CdTe single-crystalline monodisperse powders in cad mium chloride flux modified by adding elemental tellurium was studied for production different particle sizes (30-300 mu M). The growth of m ono-grain powders was carried out in isothermal conditions in closed e vacuated ampoules. It was found that at lower temperatures (500-650 de grees C) after maintaining the equilibrium conditions primary crystals grow mainly by deposition of material from saturated solution onto sm ooth surfaces of crystals. In higher temperature region (700-800 degre es C) there occurs remarkable sintering of particles and grains loose their round shape. The activation energy for volume growth Delta E(vol ) = 0.9 eV was found. Te in flux was found to prevent the formation of aggregates through sintering and to increase the crystal growth veloc ity.