Organometallic Azides as Precursors for Aluminum Nitride Thin Films

A new route to thin films of metal nitrides employing organometallic azides as the source of nitrogen is described. Depositions of AIN on several substrates at temperatures as low as 400 °C are reported by using dialkylaluminum azides. The depositions were conducted by using two separate reactors. The first was a diffusion-pumped, all-glass horizontal reactor that generated samples used for thickness measurements, microscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The second system allowed experiments to be conducted in an antechamber appended directly to an X-ray photoelectron spectrometer (XPS). The XPS data indicated that the formation of AIN had occurred and suggests that in the case of the diethylaluminum azide some unreacted azide precursor remained on the surface. Comparisons are made to a related amido precursor [Et₂AlNH₂]₃.