| Research Abstract |
Pt/Co metallic multilayrs, a combination of a ferromagnetic metal Co and a noble metal Pt, and Pt thin films, as a fundamental unit of the multilayrs, were grown on Si (111) (7x7) substrate by molecular beam deposition method, and were studied about state of the substrate, crystal growth, surface topograph, inferior structure of the films, and role of Cu buffer layr, which give a great influence on epitaxial growth of the multilayrs. Interface structures are also studied on nanometer-scale, and the relations between such the structures and electronic properties were discussed.
The studies with scanning tunneling microscopy, atomic force microscopy and transmission electron microscopy show that (i) Cu silicides are formed uniformly at Cu/Si interface, (ii) the Pt film keeps a single crystal in the depth direction, and (iii) the Pt film dose not have any pin hole and maintains high quality. It is concluded that the Pt films are suitable for a seeded layr.
A Pt/Co multilayr was successfully grown epitaxially on the Si substrate with the Pt seeded layr and the Cu buffer layr by molecular beam deposition method under clean atmosphere of ultra-high vacuum condition. On crystal growth of the Pt/Co multilayr, both Pt on Co and Co on Pt are pseudomorphic, and hence Pt/Co multilayr contained elastic strain inside and showed superior perpendicular magnetoanisotropy.
As to study on electronic properties of the Pt films and the Pt/Co multilayr, surface and interface effects in the electron transport are evaluated using a simulated model of electronic circuit. Increase of electrical resistivity induced by the interface was 65% of interior of multilayr.
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