Structural modifications of laser deposited Fe-Al multilayers due to thermal treatment

Fe-Al multilayers with nominal composition 5 . (5 nm Al-5 nm Fe), prepared by pulsed laser deposition, were investigated to study the thermal behavior caused by annealing at temperatures ranging between 100 and 300 degrees C under a controlled atmosphere. The layer parameters were studied by means o f X-ray reflectometry and wide angle X-ray scattering. As-deposited multila yers consisted of amorphous aluminum and crystalline iron layers. Pronounce d interdiffusion of Fe and Al atoms starts at an annealing temperature of a bout 150 degrees C preferably at the Fe-Al interfaces. At the same temperat ure the formation of an intermetallic phase FeAl was observed. This compoun d comprises the entire multilayer after final annealing above 250 degrees C . (C) 2000 Elsevier Science S.A. All rights reserved.