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Ion irradiation damage in ilmenite at 100 K

J.N. Mitchell·N. Yu·R. Devanathan·K.E. Sickafus·M.A. Nastasi·Gordon L. Nord
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Abstract

A natural single crystal of ilmenite (FeTiO3) was irradiated at 100 K with 200 keV Ar2+. Rutherford backscattering spectroscopy and ion channeling with 2 MeV He+ ions were used to monitor damage accumulation in the surface region of the implanted crystal. At an irradiation fluence of 1 ?? 1015 Ar2+/cm2, considerable near-surface He+ ion dechanneling was observed, to the extent that ion yield from a portion of the aligned crystal spectrum reached the yield level of a random spectrum. This observation suggests that the near-surface region of the crystal was amorphized by the implantation. Cross-sectional transmission electron microscopy and electron diffraction on this sample confirmed the presence of a 150 nm thick amorphous layer. These results are compared to similar investigations on geikielite (MgTiO3) and spinel (MgAl2O4) to explore factors that may influence radiation damage response in oxides.

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Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and AtomsArticle

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J.N. Mitchell, N. Yu, R. Devanathan, K.E. Sickafus, M.A. Nastasi, Gordon L. Nord. 1997. Ion irradiation damage in ilmenite at 100 K. https://doi.org/10.1016/s0168-583x(96)01140-8

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