AFM and XPS analysis of the AlN thin film on the Si substrate

Aluminum nitride thin film has been deposited on Si (111) substrate by using a DC magnetron sputtering system. The crystalline structure and orientation of the AlN film were studied by X-ray diffraction (XRD). Surface morphology of the film was observed by atomic force microscopy (AFM). The surface compositions and chemical environments of the film were characterized by X-ray photoelectron spectroscopy (XPS). The film shows a excellent preferred orientation of (100) and its' FWHM is 0.3°. Surface roughness parameters were Ra = 0.23 nm, RMS = 0.30 nm and Rz = 3.25 nm. XPS data show that Al, N, C, O elements were existed on the surface of the AlN film. C1s and O1s binding energy indicate that the two elements mainly existed by physically adsorbed. Al2p and N1s binding energy prove the formation of the AlN film. The XPS depth profile analysis indicates that the film present a composition highly close to AlN stoichiometric.