Magneto-transport properties of [Co/Bi]n wire structures

The present study examines the artificial control of grain-boundary resistance and its contribution to the magneto-transport properties of [Co(1 nm)/Bi(2.5 nm)]n (n=10 or 20) line structures on the Si(0 0 1)/SiNx substrate. Conventional patterning and deposition processes are applied for the fabrication of a device that consists of five-line structures with a line width of 2 μm. A ΔR/R=80% ratio was observed in the five-line structure of [Co(1 nm)/Bi(2.5 nm)]10 multilayers at 10 K. Our measurements indicate that grain-boundary effects can be associated with the large ΔR/R ratio of transverse magnetoresistance.