REACTIVE LASER ABLATION SYNTHESIS OF NANOSIZE ALUMINUM NITRIDE

An aluminum (Al) target was laser ablated in a nitrogen (N2) atmosphere, producing aluminum nitride (AlN) powder. These powders were calcined at 900-degrees-C for 2 h. Powders were produced at various nitrogen pressures, and the calcined powders were tested for unreacted aluminum content, using differential thermal analysis (DTA). The AlN powder, produced at a laser fluence of 12 J/cm2 and a nitrogen pressure of 10.0 kPa (75 torr), showed no evidence of unreacted aluminum by DTA and was phase-pure AlN by X-ray diffraction (XRD). The surface area of this powder is 82 m2/g, corresponding to a particle size of approximately 11 nm, which is in good agreement with TEM observations.