No abstract

No abstract

In this paper the effect of the growth temperature on the structural and electrical properties of samarium silicide films is investigated. The growth of the epitaxial films is performed under ultrahigh vacuum by reactive-deposition epitaxy on silicon (0 0 1) substrates. The structural properties are assessed by reflection high-energy electron diffraction and x-ray diffractometry. Random and channelling Rutherford backscattering experiments show that the films have the correct stoichiometry, i.e. Sm/Si ratio = 1 : 2, with channelling yields as low as 20% for the best samples. The electrical properties of these films are studied by Hall effect and resistivity measurements. The films have a metallic character, with a high concentration of n-type charge carriers (>10 22 cm −3) and a resistivity lower than 200 µ cm at room temperature. The metallic character is confirmed by the experimental optical conductivity deduced from ellipsometry experiments. Finally, evidence is presented showing the potential of SmSi 2 /n-type Si junctions for electronic application with a Schottky barrier height of about 0.32 eV.

We observe a large magneto-resistance in very thin Ba2FeMoO6films of ~-12% at 10K, which is not significantly changed when thin NiFe/Ba2FeMoO6bi-layers are made. This suggests that the magneto-resistance in both cases is dominated by inter-grain tunnelling in the Ba2FeMoO6thin film. There is an anomalous peak in the resistance at ~300K in the bi-layer film that can not be easily explained. However, we know that the temperature where this peak occurs is close to the Ba2FeMoO6Curie temperature.