Growth of CdTe monograin powders

The preparation of CdTe single-crystalline monodisperse powders in cadmium chloride flux modified by adding elemental tellurium was studied for production different particle sizes (30-300 μm). The growth of monograin powders was carried out in isothermal conditions in closed evacuated ampoules. It was found that at lower temperatures (500-650 °C) after maintaining the equilibrium conditions primary crystals grow mainly by deposition of material from saturated solution onto smooth surfaces of crystals. In higher temperature region (700-800 °C) there occurs remarkable sintering of particles and grains loose their round shape. The activation energy for volume growth ΔEvol = 0.9 eV was found. Te in flux was found to prevent the formation of aggregates through sintering and to increase the crystal growth velocity.