Influence of pressure on the properties of AlN deposited by DC reactive magnetron sputtering on Si (100) substrate

Preferred (002)-oriented aluminium nitride (AlN) films by direct-current (DC) magnetron sputtering on Si (100) substrate were prepared at various deposition pressure (0.12-0.5 Pa). The influence of pressure on the surface morphology, crystal structure and optical properties of AlN thin films was discussed the with the methods of X-ray diffraction, atomic force microscopy and stress analyser, respectively. Optical properties were studied by ellipsometer and Fourier transform infrared spectrometer. It was observed that the AlN films tended to be preferred (002)-oriented when the pressure was decreased and the value of full width at half maximum is 0.325 degrees when the pressure was kept at 0.12 Pa. the tensile stress, refractive index, and the density of Al-N bonds decreased with increasing the sputtering pressure from 0.12 to 0.5 Pa. This work demonstrated the influence of sputtering pressure on the structural and optical properties of the AlN films deposited on Si (100) substrate, the gallium nitride epitaxial film on Si (100) substrate was expected to be realised using sputtered AlN as the buffer layer.