FIGURE 2 SEM planar image and EDS spectra of dark grey AlN
powder sample: (a) SEM image; (b) and (c) EDS spectra of square areas 1
and 2 in Figure a, respectively
The surface morphology of the dark grey AlN powder sample is shown in
Figure 2a. The AlN particles are mostly spherical, where a portion
agglomerate to form big secondary particles. EDS tests show that the
smooth particle contain only Al and N elements (Figure 2b),
corresponding to pure AlN particles. In contrast, the rougher particles
contain higher C and O contents, along with the Al and N elements
(Figure 2c). In these samples, C and O impurities exist, due to the
incomplete synthesis of AlN.
Mesophase