Effects of High Magnetic Field and Post-Annealing on the Evaporated Ni/Si (100) Thin Films

The effects of high magnetic field and post-annealing on the structural, electrical and magnetic properties of the evaporated Ni films were investigated and compared. The in-situ application of a 6 T magnetic field during evaporation or post-annealing at 200 degrees C did not change the crystal structures of the films. However, the magnetic field makes the films exhibit the smallest grain size and the lowest surface roughness. Crystallinity was improved for both the 6 T films and the annealed films. This leads to the enhancement of saturation magnetization (Ms). The value of Ms for the 0 T films was 588 emu/cm(3), while those for the 6 T films and the post-annealing films without magnetic field were 704 and 647 emu/cm(3), respectively. In addition, the 6 T films also exhibited the lowest resistivity. These results indicate that the in-situ application of high magnetic field was a much more efficient method than the post-annealing treatment in the increase of film quality and properties.