S. Bhagwat et al., THERMALLY-INDUCED TRANSFORMATIONS AT AN ION-IMPLANTED ALPHA-FE2O3 ALPHA-AL2O3 INTERFACE - A MOSSBAUER-SPECTROSCOPY STUDY/, Journal of applied physics, 79(8), 1996, pp. 4141-4145
Thermally induced chemical transformations at the interface between a
100 nm alpha-Fe2O3 and a polycrystalline alpha-Al2O3 substrate are stu
died and compared for the cases of the as-formed and ion bombarded int
erfaces. The thermal annealings are carried out under vacuum at 450 de
grees C for different time durations and the transformations are exami
ned by conversion electron Mossbauer spectroscopy. It is shown that in
the sample prebombarded with 110 keV Ar+ ions, the formation of Fe3-x
AlxO4, FeAl2O4, and FeO phases is favored at variance with a nonbombar
ded sample in which primarily a defective Fe3O4-y phase is produced wi
th some amount of FeO. This difference is explained in terms of the an
nealing process of the oxygen vacancies produced during Ar implantatio
n near the interfacial region. (C) 1996 American Institute of Physics.