REACTION STUDY OF ALUMINUM-CHLORIDE WITH AMMONIA AND MECHANISMS LEADING TO ALUMINUM NITRIDE

The compound formed between AlCl3 and NH3 at room temperature and low temperature, characterized by different analysis methods, corresponds to the formula AlCl3 . 6NH(3). This intermediate was heated to 900 deg rees C under an ammonia stream to obtain aluminium nitride in low yiel d; as by-product NH4Cl was formed during the thermolysis. In order to explain the decomposition mechanisms, two new pyrolysis were realized, under nitrogen and under reduced pressure. These showed formation of Al(NH2)NH in addition to NH4Cl during the thermal decomposition. Al(NH 2)NH can react with HCl, which results from the dissociation of NH4Cl, to form AlClNH volatile combination. This is cararied out by the gase ous stream during the thermolysis, thereby accounting for the low synt hesis yield.