The Magnetoresistance of Nanostructured Co-ZnO Films with ZnO Buffer-Layers


Co-ZnO films were prepared on oxidised silicon by magnetron sputtering at room temperature both with and without a ZnO buffer-layer. The Co-ZnO films consisted of Co particles dispersed in a semiconductor matrix. The combination of a Co-ZnO layer and a ZnO buffer-layer has a higher magnetoresistance than the Co-ZnO layer alone on an insulating Si substrate. The causes of this effect were investigated using X-ray photoelectron spectroscopy, depth profiling using Auger electron spectroscopy and electrical resistance as well as measurements of the change in the saturation magnetisation, the field cooled- and zero field cooled-magnetisation. This work has shown clearly what criteria are needed to optimise the magnetoresistance and how these conditions may be met by adding a buffer-layer thus making granular films based on ZnO more suitable for applications as field sensors.

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Li, X. , Cheng, L. , Cheng, L. , Wang, Y. , Gao, Y. , Quan, Z. , Qin, X. , Blythe, H. , Gehring, G. and Xu, X. (2014) The Magnetoresistance of Nanostructured Co-ZnO Films with ZnO Buffer-Layers. Materials Sciences and Applications, 5, 996-1003. doi: 10.4236/msa.2014.514101.

Conflicts of Interest

The authors declare no conflicts of interest.


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