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arXiv · cond-mat/0401569

Electrical and structural properties of MgB2 films prepared by sequential deposition of B and Mg on the NbN buffered Si(100) substrate

Abstract

We introduce a simple method of an MgB2 film preparation using sequential electron-beam evaporation of B-Mg two-layer (followed by in-situ annealing) on the NbN buffered Si(100) substrate. The Transmission Electron Microscopy analyses confirm a growth of homogeneous nanogranular MgB2 films without the presence of crystalline MgO. A sensitive measurement of temperature dependence of microwave losses shows a presence of intergranular weak links close the superconducting transition only. The MgB2 films obtained, about 200 nm thick, exhibit a maximum zero resistance critical temperature of 36 K and critical current density of 3x10^7 A/cm^2 at 13.2 K

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S. Chromik, S. Gazi, V. Strbik, M. Spankova, I. Vavra, L. Satrapinsky, S. Benacka, C. J. van der Beek, P. Gierlowski. 2004-01-28. Electrical and structural properties of MgB2 films prepared by sequential deposition of B and Mg on the NbN buffered Si(100) substrate. https://doi.org/10.1063/1.1794357

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