STUDY OF PRODUCTS FORMED FROM THE REACTIO N BETWEEN ALUMINUM HALIDES AND AMMONIA DURING ALUMINUM NITRIDE SYNTHESIS

In recent years, the aluminum nitride synthesis turns towards ultrafin es powders free from oxygen in order to realize substracts for news hy brid circuits. The synthesis by ammonolysis of halides compounds is a possible way. The reaction between AlX3 (X : halogen) and NH3 leads to AlX3, 6 NH3 formation at both room temperature and low temperature (T : -50-degrees-C). Low temperature studies in liquid ammonia have show n that AlCl3, 6 NH3 is an addition compound whereas AlBr3, 6 NH3 and A lI3, 6 NH3 formulations represent respectively the following mixtures : AlBr2(NH2), 4 NH3 + NH4Br, AlI(NH2)2, 2 NH3 + 2 NH4I. NH4X which is soluble in liquid ammonia interacts with AlBr2(NH2), 4 NH3 and AlI(NH2 )2, 2 NH3 compounds to form soluble complexes.