The present work reports the growth of aluminum nitride (AlN) thin film aiming its application in the manufacturing of microsensors devices based on surface acoustic waves (SAW). The AlN thin films were deposited on p-type silicon (100) substrate by radio frequency magnetron sputtering technique. The plasma parameters were varied in order to investigate the best set ups to growth AlN thin films for application in SAW devices. The parameters explored were residual pressure, nitrogen concentration and applied RF power. These parameters had strong influence in the structure and composition of the deposited AlN films. The deposition rate and morphology were characterized by mechanical and optical profilometries and the field emission gun scanning electron microscopy, respectively. The deposition rate linearly increases with the increase of the RF power up to about 240W. For higher RF power the deposition rate presents a less accentuated increase probably due to the retro-sputtering of the growing film caused by the high energetic species impinging the film surface. High nitrogen content (100%) in the gas mixture decreases the deposition rate by about 50% assumed that it occurs due to the target poisoning. The crystalline structures of the deposited AlN thin films were analyzed by X-ray diffraction, Raman spectroscopy and variable angle spectroscopic ellipsometry. The film crystallinity and composition are tightly influenced by the residual pressure in the deposition chamber due to the elevated concentration of impurities, mainly oxygen. The increase of the applied RF power favors the growth of well oriented h-(002) hexagonal wurtzite type structure. The refractive index values obtained are in good agreement with the values described in the literature and the values increase with the increase improvement of the AlN crystallinity, that occurs with the increasing of the applied RF power. The bandgap energies values obtained by ellipsometry was slightly low compared with the bandgap energy values obtained by the Tauc-Lorentz method that is closer to the values cited in the literature. This difference was caused by the lack of good model fit, once the used model does not take into account the strong absorption of the AlN thin film for photon energy higher than 4.5 eV. The AlN film with the best set of properties for SAW application was grown with lower residual pressure in the plasma chamber, gas mixture containing 70% of N2 and an RF power of 240W.