Planar Hall Voltage Properties Of Ta/Nife/Ta/Nife/Ta Multilayer For Biosensor Applications

Recently, magnetic nanoparticles and planar Hall resistance (PHR) devices used in biomolecule diagnosis and biological applications have attracted considerable attention as biosensors. The voltage properties of a planar Hall device with a Ta/NiFe/Ta/NiFe/Ta multilayer that was prepared in a cross-shaped pattern at a width of 0.5 mm using a shadow mask, were investigated. The sensitive planar Hall voltage (SPHV) obtained from the planar Hall voltage (PHV) curves of a Ta(5 nm)/NiFe(6 nm)/Ta(t = 2-8 nm)/NiFe(6 nm)/Ta(5 nm) multilayered sample was a few mV/Oe in the fine magnetic field region of the external magnetic field of 1.0 Oe. In particular, the thickness of Ta(t = 8 nm), the PHR ratio, magnetic sensitivity, and SPHV improved significantly by as much as 36.4 %, 28 %/Oe, and 1.6 mV/Oe, respectively. These results can be used in the development of a PHR biosensor with a high sensitivity for the detection of nanoparticle-antibody binding, even in a simple structure formed only out of a ferromagnetic NiFe layer.