Structural study of nanometer-sized iron crystallites in single crystalline iron-MgO composite films.
Single crystalline composite films of iron and MgO are prepared by a simultaneous vacuum deposition technique. The structures of the composite films, especially of the iron crystallites embedded, are studied by high-resolution electron microscopy and nanometer-area electron diffraction. The alpha-iron (b.c.c.) crystallites of 1 nm in size are epitaxially embedded in single crystalline MgO films, the orientation being (011)[100]Fe parallel (001)[100]MgO and (001)[110]Fe parallel (001)[100]MgO. A heat treatment of the as-grown films at 500-1,000 degrees C brings about a phase transformation of the crystallites from alpha-iron to gamma-iron (f.c.c.), followed by a grain growth of alpha-iron and finally the growth of the spinel, MgFe2O4. The gamma-iron crystallites transformed are circular plates and have strains at the periphery to accommodate the surrounding MgO-matrix. The magnetic property of the composite films is also reported.
Tanaka
N
N
Department of Applied Physics, Faculty of Engineering, Nagoya University, Japan.
Nagao
M
M
Yoshizaki
F
F
Mihama
K
K
D055598:Chemical Phenomena; D002621:Chemistry; D003460:Crystallization; D007501:Iron / Q000032:analysis*; D008277:Magnesium Oxide / Q000032:analysis*; D008854:Microscopy, Electron / Q000379:methods; D015394:Molecular Structure; D014961:X-Ray Diffraction
D008277:Magnesium Oxide; D007501:Iron