AGING OF FE-AL THIN-FILM MULTILAYERS

Multilayers constituted by very thin films of Fe and Al, deposited by thermal evaporation and magnetron sputtering techniques and then aged in air at temperatures in the 300-400 K range for times up to 200 h, were analyzed by means of XRD, CEMS, XPS and AES measurements. Fe(Al) solid solutions form during evaporation because of interdiffusion phenomena at the Fe-Al interfaces, while Al undergoes oxidation during sputtering deposition and, consequently, the multilayers are constituted by Fe intercalated with Al2O3 films. Aging treatments in oxidizing environments induce no significant modification in sputtered multilayers while, on the contrary, the evaporated multilayers show the effects of both interdiffusion and oxidation phenomena.