Aluminum nitride powders, properties

The surfaces of oxide nanopowders have been extensively studied either for characterization purposes or for potential catafytic properties investigatioa As for non-oxide ceramic powders, references on their surface studies are scarce. Due to hydrolysis in ambient atmosphere, the unavoidable presence of oxygen in the first atomic layer of these nanostructured powders may drastically modify their expected properties. After briefly introducing our characterization technique of nanosized powder sur ces, we will present as an exan le, the Fourier transform infixed (FT-IR) sur ce analysis of a nanostructured aluminum nitride powder obtained via sol-gel type chemical synthesis. 

I 9 AIN Ceramics from Nanosized Plasma Processed Powder, its Properties and Application Table 9.1 Characteristics of aluminum nitride ceramics. 

When AIN was introduced for electronic packaging applications in 1985 it was considered inconsistent in properties. This inconsistency was due to problems with the AIN powders used to make sintered products. The powders were made by either of two methods direct nitridation of aluminum metal in a nitrogen gas atmosphere or carbothermal reduction of alumina, which involves the decomposition of the reaction product of aluminum trichloride with ammonia. The first process was cheaper, but the resultant powders were not especially well suited to materials for electronic applications. The carbothermal process produces powders of greater uniformity and purity, with greater control over size and shape, than the nitridation process, and is the more widely used process today." ... 

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