Influence of the microstructure on the magnetism of Co-doped ZnO thin films
arXiv:cond-mat/0604468 · doi:10.1063/1.2206091
Abstract
The prediction of ferromagnetism at room temperature in Co-ZnO thin films has generated a large interest in the community due to the possible applications. However, the results are controversial, going from ferromagnetism to non-ferromagnetism, leading to a large debate about its origin (secondary phase, Co clusters or not). By carefully studying the micro-structure of various Co-ZnO films, we show that the Co2+ partly substitutes the ZnO wurtzite matrix without forming Co clusters. Surprisingly, the ferromagnetism nature of the films disappears as the Co content increases. In addition, our results suggest that the observed ferromagnetism is likely associated to a large amount of defects- close to the interface and strongly depending on the growth temperature- which may explained the spreading of the results.
arXiv comment4 pages, 4 figures, to be published in Journal of Applied Physics (2006)
References in corpus (10)
- Absence of ferromagnetism in Co and Mn substituted polycrystalline ZnO
- Co-occurrence of Superparamagnetism and Anomalous Hall Effect in Highly Reduced Cobalt Doped Rutile TiO2 Films
- Ferromagnetism in laser deposited anatase TiCoO$_{2-$δ$}$ films
- Formation of Co nanoclusters in epitaxial Ti_{0.96} Co_{0.04} O_2 thin films and their ferromagnetism
- Laser ablation of Co:ZnO films deposited from Zn and Co metal targets on (0001) AlO substrates
- Absence of room temperature ferromagnetism in bulk Mn-doped ZnO
- Magnetism in Cobalt doped Cu2O thin films without and with Al, V, Zn codopants
- Compensation, interstitial defects and ferromagnetism in diluted semiconductors
- Investigation of laser ablated ZnO thin films grown with Zn metal target: a structural study
- Structural and magnetic properties of a series of low doped ZnCoO thin films deposited from Zn and Co metal targets on (0001) AlO substrates