Abstract
Zinc-oxide (0001) single crystals with a 0.5 mm thickness were prepared, and then 80 keV Fe ions with a dose of 3 × 1016 ions/cm 2 were implanted into the ZnO single crystals at 350°C The implanted samples were post-annealed at 700, 800 and 900°C by rapid thermal annealing in an N2 atmosphere for 5 min to remove the ion-implantation damage. The structure and the magnetic properties of Fe-ion-implanted ZnO were investigated by using X-ray diffraction and a superconducting quantum interference device magnetometer. The carrier transport properties were measured in the range from 5 K to 300 K. The X-ray diffraction results showed an island peak near 37°C, which was identified as ZnO 2. The magnetization curve showed hysteresis loops at 5 K in the samples annealed at 700 and 800°C, showing ferromagnetism. Hysteresis loops were observed at 300 K in the samples annealed at 700°C The temperature dependence of the magnetization was taken in field cooling (FC) and zero field cooling (ZFC) in the samples annealed at 700°C The difference magnetization (ΔM) between the FC and the ZFC magnetizations did not converge to a zero value even at 340 K, showing ferromagnetism above room temperature. The magnetoresistance (MR) curve showed negative curvature up to 150 K which could be explained with the delocalized d state of ZnO implanted with Fe ions.
Original language | English |
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Pages (from-to) | 1706-1710 |
Number of pages | 5 |
Journal | Journal of the Korean Physical Society |
Volume | 50 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2007 Jun |
Keywords
- Fe-implanted ZnO
- Ferromagnetism
ASJC Scopus subject areas
- Physics and Astronomy(all)