Room temperature magnetism in semiconducting films of ZnO doped with ferric ions

Films consisting of Zn1-xFexO were prepared by alternating-target laser ablation deposition. The Fe doping levels ranged from x=0.016 to 0.125 at. %. X-ray diffraction and energy dispersive x-ray spectroscopy measurements showed only (002n) reflections of the ZnO host and confirmation of the Fe concentration, respectively. For films grown on (001) Al2O3 at 300 K, room temperature average saturation magnetization, < 4 pi M-s >, measured from superconducting quantum interference device (SQUID) hysteresis loops for x=0.125 +/- 0.025 was 172 G. Although SQUID measurements were sensitive to the average value of the saturation magnetization, ferrimagnetic resonance measurements appeared to be sensitive only to the saturation magnetization of the so-called magnetic layer containing ferric ions. We believe that we have produced a host semiconductor material doped with impurities of ferrimagnetic ordering. (C) 2006 American Institute of Physics.