The influence of the ion implantation process on the charge state of dilute Fe-57 impurities implanted as radioactive Mn-57 in ZnO is investigated by Fe-57 emission Mossbauer spectroscopy. One sample is additionally implanted with stable Na-23 impurities. Both Fe2+ and Fe3+ charge states are observed, and the Fe3+/Fe2+ ratio is found to increase with the fluence of both Mn-57/Fe-57 and Na-23 ions, demonstrating that the build-up of Fe3+ is not related to the chemical nature of the implanted ions. The results are interpreted in terms of radiation damage induced changes of the Fermi level, and illustrate that the Fe3+/Fe2+ ratio can be adjusted by ion implantation. The spin-lattice relaxation time for Fe3+ in ZnO is found to be independent of the implantation fluence, and is evidently an intrinsic property of the system.
Mantovan, R., Gunnlaugsson, H., Naidoo, D., Olafsson, S., Johnston, K., Masenda, H., et al. (2012). Fe charge state adjustment in ZnO upon ion implantation. JOURNAL OF PHYSICS. CONDENSED MATTER, 24(48) [10.1088/0953-8984/24/48/485801].
Fe charge state adjustment in ZnO upon ion implantation
FANCIULLI, MARCO;
2012
Abstract
The influence of the ion implantation process on the charge state of dilute Fe-57 impurities implanted as radioactive Mn-57 in ZnO is investigated by Fe-57 emission Mossbauer spectroscopy. One sample is additionally implanted with stable Na-23 impurities. Both Fe2+ and Fe3+ charge states are observed, and the Fe3+/Fe2+ ratio is found to increase with the fluence of both Mn-57/Fe-57 and Na-23 ions, demonstrating that the build-up of Fe3+ is not related to the chemical nature of the implanted ions. The results are interpreted in terms of radiation damage induced changes of the Fermi level, and illustrate that the Fe3+/Fe2+ ratio can be adjusted by ion implantation. The spin-lattice relaxation time for Fe3+ in ZnO is found to be independent of the implantation fluence, and is evidently an intrinsic property of the system.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.