Growth and morphological evolution of c-axis oriented AlN films on Si (100) substrates by DC sputtering technique

Aluminum nitride (AlN) films were grown on Si substrates by dc magnetron sputtering in plasma containing a mixture of argon and nitrogen, using a pure aluminum target. In this paper, we studied the growth of AlN films on Si(100) substrates under varying gas ratio (N2 to Ar gas ratio) by DC reactive magnetron sputtering at moderate deposition temperature (400°C-600°C). Phase formation and orientation of the thin films were determined by Grazing Incidence X-Ray Diffraction (GIXRD). Surface morphology of the deposited thin films was investigated by Scanning Electron Microscope. Film orientations were studied by varying the gas ratio and deposition temperature to obtain (002) oriented film. The highest Texture coefficient along (002) direction (γ=3.2) is obtained for optimized growth condition at Argon to Nitrogen gas ratio 10:10 and substrate temperature 550°C. This oriented film can be used in MEMS based devices.