INPLANE PERIODIC BICRYSTALLINITY IN MAGNETIC THIN-FILMS

Magnetic thin films have been deposited by molecular beam epitaxy on v icinal Si(111) substrates misoriented towards [11-2]. The substrates w ere thermally pretreated in order to activate the step bunching mechan ism, which results in a laterally modulated surface topology with a pe riod of similar to 800 Angstrom. Cobalt or permalloy layers grown on s uch surfaces exhibit an in-plane uniaxial magnetic anisotropy. This an isotropy is associated with the lateral pseudoperiodic variation of th e crystalline orientation of the metallic layers as observed by transm ission electron microscopy. Magnetoresistance measurements on microstr uctured films reveal a single-domain behavior with a magnetization rev ersal by rotation. (C) 1996 American Institute of Physics.