Perpendicular current magnetoresistance in Co/Cu/NiFeCo/Cu multilayered microstructures

An approach is demonstrated for lithographic fabrication of perpendicular current magnetoresistance devices which avoids the necessity of postprocess ‘‘trimming’’ of electrical leads. Magnetoresistance properties are investigated as a function of device size, magnetic layer thickness, and temperature. It is found that in some cases the current distribution in the microstructures change substantially with temperature resulting in a negative temperature coefficient of resistivity. It is also shown that the devices’ own magnetic fields have a dramatic effect on magnetoresistance properties.