AlN dielectric thin films were deposited on N type Si(100) substrate by reactive radio frequency magnetron sputtering that directly bombardment AlN target under different sputtering-power and total pressure. The crystal structure,composition,surface and refractive index of the thin films were studied by XRD, SEM, AFM and elliptical polarization instrument. The results show that the surface and refractive of the thin films strongly depends on the sputtering-power and total pressure,the good uniformity and smoothness is found at 230 W, Ar flow ratio 5.0 LAr/sccm, substrate temperature 100°Cand 1.2 Pa. The crystal structure of the as-deposited thin-films is amorphous，then it transforms from blende structure to wurtzite structure as the rapid thermal annealing(RTA) temperature changes from 600 to 1200°C. The refractive index also increases with the RTA temperature it is increasing significantly from 800 to 1000°C．

Using the radio frequency magnetron sputtering that directly bombardment A1N target under different sputtering-power and total pressure to deposit the A1N thin films. The crystal structure, composition, surface and refractive index of the thin films were studied by XRD, SEM, AFM and elliptical polarization instrument. The results show that the surface and refractive of the thin films strongly depends on the sputtering-power and total pressure,the good uniformity and smoothness is found at 225 W, Ar flow ratio 5.0 LAr/sccm, substrate temperature 100°Cand 1.2 Pa. All film thickness are from 60 to 80nm, and the highest N/Al mole ratio reach to 0.83.The crystal structure of the as-deposited thin-films is amorphous，then it transforms from blende structure to wurtzite structure as the rapid thermal annealing(RTA) temperature changes from 600 to 1200°C. The refractive index also increases with the RTA temperature it is increasing significantly from 800 to 1000°C. When the Annealing temperature at 1000°C, we get the best uniformity and smoothness of the surface of the film.