Design and Material Optimization of Magnetic Flux Concentrator for Enhanced Field Sensitivity of Magnetoresistive Sensor

Abstract

MFC (Magnetic Flux Concentrator) is located around the sensor to guide the magnetic field and concentrate it on the sensor. This research developed MFC which thickness doesn’t exceed few micrometers and low hysteresis. The optimized value of the distance between the MFC poles was determined by magnetic simulation. Research has propose structures with small coercivity of MFC. Single-layer (Ta/NiFe/Ta) MFC, bilayer (Ta/NiFe/IrMn/Ta) MFC and trilayer ((Ta/NiFe/Cu/IrMn)n/Ta) MFC are compared. Significant reduction in coercivity has been demonstrated for both bilayer and trilayer MFC compared to single-layer MFC. In order to enhance the amplification factor, trilayer structure was repeated several times to increase the ferromagnetic layer thickness, and the effect of the number of repetitions was investigated.