Effects of Different Nitrogen Flow Rates on Structure and Optical Characteristics in AlN Films by Reactive Magnetron Sputtering

AlN coatings were deposited on Si (100) substrates by reactive magnetron sputtering with nitrogen-to-argon flow ratios being varied. The main focus of this study was to analyze and provide a theoretical explanation for how the N 2 flow ratio affects the crystal structure, surface morphology, and optical properties of films oriented along the C-axis. The findings indicated that AlN films displayed the highest level of stability and premium quality when the N 2 flow ratio was set at 40%. X-ray diffraction analysis demonstrated prominent (002) diffraction peaks for AlN films obtained at varying N 2 flow levels between 20% and 50%. Furthermore, the examination conducted via scanning electron microscopy demonstrated that higher N 2 flow ratios resulted in an improved structural order of the films on the (002) crystal plane, ultimately leading to enhanced preferred orientation. Through the manipulation of the N 2 flow ratio, the deposition rate and optical characteristics were effectively improved. These findings have significant implications for improving the crystalline quality of AlN films made through sputtering. Furthermore, this study explores the relationship between the N 2 flow ratio and performance parameters of the films, which facilitates their application in optoelectronic and electronic devices.