Hybrid AMR/PHR ring sensor

The AMR (anisotropic magnetoresistance) and PHR (planar Hall resistance) contribution was analyzed for fabricated ring type sensor junctions in single and multiring bridge sensors, and their field sensitivity was examined. The voltage profile, i.e. the sum of AMR and PHR effects, reveal anti-symmetric behavior with the magnetic field with small offsets due to the self-balancing of ring arm resistances, but the voltage variations for the external field are additive for all junction components. The field sensitivity of the resistance for a single ring sensor is 9.5mΩ/Oe, and its value monotonously increased to 102.6mΩ/Oe for 17 rings with an enhanced active area.

► Hybrid AMR–PHR ring sensor is fabricated for enhanced field sensitivity and active sensor area.
► The sensor is able to measure an average quantity of biofunctionalized labels.
► The field sensitivity of a single ring sensor is 9.5mΩ/Oe which can be increased to 102.6mΩ/Oe by 17 rings.