STOICHIOMETRY OF PURE AND Bi-SUBSTITUTED YTTRIUM IRON GARNET FILMS PREPARED BY ION BEAM SPUTTERING
- Resource Type
- Journal Article
- Authors
- H. LE GALL; J. BEN YOUSSEF; M. DESVIGNES; M. GUILLOT; Y. DUMOND
- Source
- Journal of the Magnetics Society of Japan. 1998, 22(S_2_MORIS_97)113
- Subject
- Language
- English
- ISSN
- 0285-0192
1880-4004
Single crystalline {Y3}[Fe2] (Fe3) O12 and {Y3-x Bi-x}[Fe2] (Fe3) O12 (x ≅ 1.10) garnet thin films were deposited on either (111)-oriented gadolinium gallium garnet Gd3Ga5O12 (GGG) or (111)-Ca-Zr substituted GGG using the ion beam sputtering method. The preparation consists of two main steps : i) deposition of amorphous films ii) post-annealing for crystallization in oxygen atmosphere. Using electron microprobe analysis, the Y/Fe content ratio. R, was determined. The lattice constant of the films was deduced from X-ray diffraction studies using Cu-Kα wavelengths. Only the (444) and (888) reflection peaks were observed and for all the films studied, the [111] orientation of the single crystalline films was deduced. We find first that the angular position of the reflections lines of the magnetic layer is quasi independent of the nature of the substrate for the pure YIG films. It is concluded that only films deposited on GGG substrates are epitaxially grown. Bi-YIG films deposited on large lattice parameter substrates were found also epitixially grown. The YIG film composition is explained by the presence of Y3+ ions in the octahedral [a] site when R<0.6 and by a point-defect structure model including an oxygen vacancy and a small amount of Fe2+ ions in the dodecahedral {c}site when R<0.6.