Fabrication and Usage of a Multi-turn μ-Coil and a PR Channel Combined with a Dual-type GMR-SV Device

The dual-type GMR-SV thin films and devices with multi-turn μ-coil and PR channel for detection of red blood cell (RBC) using ion-beam deposition system and lithography process were developed and used to one biosensor. The magnetoresistance (MR) ratio of a dual-type GMR-SV device post-annealed at a temperature of 200°C was 2.5 %, the magnetic field sensitivity (MS) was 0.6 %/Oe, and the coercivity (H_c) was 0.5 Oe. An AC magnetic field was generated in the vertical direction at the center of GMR-SV device using a multi-turn μ-coil. The magnetic beads (MB) coupled to the RBCs were controlled by the AC input current applied to a multi-turn μ-coil, measured as output signal as MR variation during a staying time of 0.5 s in the GMR-SV device. This result implies that the output signal of a dual-type GMR-SV device can analyze the detection state of the RBC passing through the center of a multi-turn μ-coil and PR channel.