A set of aluminium nitride ( AlN ) and oxidized AlN ( AlNO ) thin films were grown with the technique of direct current (dc) reactive magnetron sputtering. The main purpose of this investigation is to explore the influence of the oxygen on the structural properties of AlN and AlNO films. The crystalline properties and chemical identification of phases were studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), respectively. Electrical properties were analyzed from I-V measurements. It was found that films crystallized under the AlN würzite structure and presented a polycrystalline preferential growth along [0001] direction, perpendicular to substrate. Small amounts of secondary aluminium oxide phases were detected too. The oxide phases can induce defects, which can alter crystallinity of films.

A set of AlN thin films was prepared by reactive magnetron sputtering at room temperature. The effect of oxygen impurities on the structural and optical properties of AlN films is discussed. The structural and optical properties were characterized using X-ray diffraction (XRD) and spectroscopic ellipsometry, respectively. Depending on the deposition conditions, films can grow hexagonal (würzite, P 63 m 3) or cubic (zinc-blende, Fm3m) in microstructure. From the optical measurements, the ellipsometric parameters (ψ, Δ) and the real refractive index as a function of energy were obtained. From the ellipsometric measurements, a model of Lorentz single-oscillator was employed to estimate the optical band gap, Eg. In the theoretical part, a calculation of density of states (DOS) and band structure was performed to be compared with the experimental results.

A set of AlN films were deposited by reactive direct current (DC) magnetron sputtering. Films were analyzed with X-ray diffraction and Auger Electron Spectroscopy (AES). There is a correlation between deposition parameters and crystal growth. Depending on the deposition parameters, films can present a hexagonal würzite (P6mm) or cubic zinc-blend (Fm3m) microstructure. Oxygen appears to induce on films a degree of amorphous growth and a distortion of the lattice parameters. For the film with cubic microstructure, AES transitions detected near the surface level at 56 eV and 66 eV were attributed to aluminum-oxide ( Al xOy), AlN , and metallic Al .