In order to find out the formation procedures and the serves of morphology for aluminum nitride by the vapor phase reaction, the experiments have been carried out in the temperature range of 200-1500℃ and the various pressures. The reaction products and thermal decomposited powders in the various temperatures and pressures have been thoroughly investigated by means of X-ray diffraction, and electron microscopy. Sphere shaped A1N was formed from 600℃, whereas whisker-shaped and rod-shaped A1N crystals were obtained in more than 1000℃ in the vapor phase reaction. For aluminum nitride powders, the growth of crystal was accelerated at constant pressure of 4.9 KPa. A1N formed by these reaction is changed gradually into sphere, plumule, and rod-shaped with increasing temperature. |
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