The oxidation of an aluminum nitride powder studied by bremsstrahlung-excited Auger electron spectroscopy and x-ray photoelectron spectroscopy

Bremsstrahlung-excited Auger electron spectroscopy (AES) was used to study the oxidation kinetics of an aluminum nitride powder oxidized in air at 750, 800, 850, and 900 °C. An equation was derived to calculate the average surface oxide film thickness from the aluminum AES spectra. The oxidation of this powder was found to follow a parabolic rate law within this temperature range. The measured activation energy was 230 ± 17 kJ/mol (55 ± 4 kcal/mol). Analysis with x-ray photoelectron spectroscopy (XPS) showed that in addition to the nitride N 1s peak, there was a second N 1s peak. This peak has been observed in previous studies and can be attributed to N-O bonding either within the growing oxide film or at the Al₂O₃/AlN interface.