Phase identification of cobalt ferrite/metal composite thin films using convergent beam electron diffraction

Abstract

Cobalt ferrite/metal composite thin films with a saturation magnetization (M-s) of similar to 0.729 Weber m(-2) were prepared by a reactive sputtering method. The M-s of the thin films increased with increasing substrate temperature. The microstructures of the thin films were identified by a convergent beam electron diffraction method. For the thin films deposited at high substrate temperatures ( >300 degrees C), CoxFe1-x (x approximate to 0.62) metal alloys were separated from the cobalt ferrite matrix. A cobalt ferrite phase was determined as CoFe2O4 with a cubic structure (a(0) = 0.839 nm) and a space group of Fd3m, while a metal phase CoxFe1-x (x approximate to 0.62) with a b.c.c. structure (a(0) = 0.289 nm) and a space group of lm3m. (C) 1998 Kluwer Academic Publishers.