Abstract: Using AlN powders as raw materials and CaO-B₂O₃ as additives, AlN whiskers were fabricated by a sublimation-recrystallization
method. The influences of reaction chamber’s structure and temperature gradient on AlN synthetics were inspected, as well as the fabrication mechanism
and growth characteristics of AlN whiskers. At the earlier stage of reaction, different morphologies of AlN synthetics such as crystal pillars,
whiskers and noncrystalline fibers were produced by VLS mechanism. While at the later stage, VS mechanism occurred, which yielded only AlN
whiskers. By XRD and TEM analysis, it was discovered that most AlN whiskers grew on crystal planes {2110}, {101l} and {0001}, along crystal axes [2110], [101w]
and [0001], l=0, 1, 2 and 3, w=0, 1, 2 and 3. But in some whiskers, oblique growth was observed, therefore nonnormality of macroscopic growth
direction to growth crystal plane existed.

Key words: aluminium nitride whisker, sublimation-recrystallization method, orientation