FE-56(+)-ION IMPLANTATION EFFECTS IN AL2O3

Single and polycrystalline Al2O3 were implanted at room temperature wi th 60 keV Fe-56(+) ions with the dose range from 2.0 X 10(16) up to 1. 2 x 10(17) ions/cm(2) using a 200 keV ion implanter. Fe-56(+)-ion impl antation effects in Al2O3 have been studied directly after by using fo ur complementary techniques: Vibrating Sample Magnetometer (VSM), Ruth erford Backscattering Spectroscopy (RES), Grazing-angle X-ray Diffract ion (GXRD) and X-ray Photoelectron Spectroscopy (XPS). The specimens i mplanted with above 6.5 x 10(16) Fe+/cm(2) showed the behavior of para magnetism or ferromagnetism which depend upon the ion dose or the size of alpha-Fe particles precipitated inside Al2O3 regardless of the cry stallinity. The precipitation of alpha-Fe has been confirmed by the gr azing-angle X-ray diffraction. From X-ray diffraction line broadening, it has been confirmed that the size of alpha-Fe particles in the sing le Al2O3 monotonically increases from 6.0 to 10.8 nm with the variatio n of the ion dose. The single Al2O3 implanted with Fe+ ions has had la rger effective magneton number and the coercivity than those of polycr ystalline Al2O3. The difference in the effective magneton number and t he coercivity with the crystallinity is due to the differences in Fe d epth profiles in the implanted layers, From XPS depth profiles, the re lative ratio of metallic Fe is increased according to the increase of Fe concentration regardless of the crystallinity but oxide states of F e were nearly constant throughout the depth profiles.