PREFERENTIAL ORIENTATION GROWTH OF AlN THIN FILMS ON Si (111) SUBSTRATES BY LP-MOCVD

Abstract

Aluminum nitride ( AlN ) thin films were deposited on Si (111) substrates by low pressure metalorganic chemical vapor deposition system. The effects of the V/III ratios on the film structure and surface morphology were systematically studied. The chemical states and vibration modes of AlN films were characterized by X-ray photoelectron spectroscopy and Fourier transform infrared spectrometer. The optical absorption property of the AlN films, characterized by ultraviolet-visible-near infrared spectrophotometer, exhibited a sharp absorption near the wavelength of 206 nm. The AlN (002) preferential orientation growth was obtained at the V/III ratio of 10,000 and the preferential growth mechanism is presented in this paper according to the thermodynamics and kinetics process of the AlN growth.