Microstructural studies of e-beam evaporated alumina thin films

Abstract

Alumina thin films of different thicknesses, e.g. 90, 120 and 150 nm, were grown on SS304 thin foil by electron beam evaporation technique. The films were post-heat treated at 500, 700 and 800°C in air and subsequently characterised by X-ray diffraction, atomic force microscopy, field emission scanning electron microscopy and X-ray photoelectron spectroscopy. The effects of thicknesses and post-heat treatment on microstructure have been studied. The deposited alumina film was almost stoichiometric. The alumina film of the lowest thickness, i.e. 90 nm post-heat treated at 700°C, showed preferential growth of nanorods and irregular polygonal nanostructures with random orientation.

Keywords:

• Alumina
• Thin film
• E-beam evaporation
• Microstructure
• Nanorods