Study On The Growth Of Preferential Orientations Of AIN Thin Films

In N₂/Ar circumstances,Al N thin films were prepared by Microwave Electron CyclotronResonant plasma enhanced radio frequency reactive magnetron sputtering of Al target on Si?111?substrate.Fourier transform infrared spectroscopy?FT-IR?,Step profiler and X-ray diffraction?XRD?were employed to characterize the chemical structure and deposition rate and crystal quality of Al N thin films.Characterization results show that:Deposition temperature,radio frequency power,working gas pressure and target-substrate distance have an important influence on the growth of Al N thin films.The energy of reaction atomic on substrate surface was enhanced with the increasing deposition temperature,and the ability of atomic migration and proliferation was improved,so the crystallization of the Al N thin film is more uniform,dense and orderly.Radio frequency power directly affects the deposition energy and deposition rate,deposition energy directly influence the crystallization and preferential orientations of the Al N thin film.Working gas pressure decides the length of mean free path of molecule,the length of mean free path of molecule indirectly affects deposition energy,and thus affects the growth of Al N film.The target-substrate distance determines the collision frequency of reaction atomic in the process of deposition and deposition rate.Fewer collision corresponding to higher deposition energy,which is conducive to the growth of?002?preferential orientation of Al N thin films.In contrast,more collision corresponding to lower deposition energy,which is not conducive to the growth of?002?preferential orientation of Al N thin films.However,when microwave power from 200 W to 400 W,microwave plasma has little impact on the preferential orientations of Al N thin film.When the microwave power increased to 500 W,plasma discharge is very strong,the re-sputtering effect of plasma is increased,so the quality of crystallization and deposition rate of Al N thin films will be declining.By studying the experimental results of target-substrate distance and microwave power,the growth characteristic of?002?preferential orientation of Al N thin films was found.The growth of preferential orientation of Al N thin films is related to deposition energy and deposition rate.Faster deposition rate is not conducive to the growth of grain of?002?preferential orientation of Al N thin films and even will be changing the preferential orientations of Al N thin films.