The Magnetoresistance of Nanostructured Co-ZnO Films with ZnO Buffer-Layers — Oak Academic Publishing
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The Magnetoresistance of Nanostructured Co-ZnO Films with ZnO Buffer-Layers
Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
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Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
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Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
1 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
2 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
3 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
4 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
5 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
6 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
7 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
8 Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
9 Department of Physics and Astronomy, University of Sheffield, Sheffield, UK
10 Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education, School of Chemistry and Materials Science, Shanxi Normal University, Linfen, China
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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