Sputtering Highly C-axis-oriented AlN films on Langasite Substrate

Highly c-axis-oriented and fine structural AIN films were successfully prepared on Langasite substrate (LGS, La₃Ga₅SiO₁₄) by RF magnetron sputtering. The crystalline structure of the films was determined by X-ray diffraction (XRD) and the surface microstructure of films was quantitatively investigated by using scanning electron microscope (SEM) and atomic force microscope (AFM). Different sputtering times (1 hr, 2 hr and 3 hr) were used to deposit the films, and the thickness of films were 0.77 mum, 1.89 mum and 2.86 mum respectively. The result exhibited the films with 0.77 mum were amorphous structures. The films with 1.89 mum were mixed-orientation AIN crystalline structures, including (002) and (103) planes. As the films thickness increased to 2.86 mum, the highly c-axis-oriented AIN crystalline structures were exhibited.