Electrical and structural properties of MgB2 films prepared by   sequential deposition of B and Mg on the NbN buffered Si(100) substrate
  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 
S. Chromik, S.Gazi, V. Strbik, M. Spankova, I. Vavra, L. Satrapinsky,   S.Benacka, C.J. van der Beek and P. Gierlowski