An Orthogonal Fluxgate-Type Magnetic Microsensor

In this paper, we present a new microfabricated orthogonal fluxgate sensor structure. The sensor consists of an electroplated copper excitation rod surrounded by an electroplated permalloy layer and has planar pick-up coils for signal detection. The use of electroplating leads to a low-cost fabrication process and the use of planar pick-up coils provides easy integration with CMOS processes. The fabricated sensor has an excitation independent linear range of ±100 μT, a sensitivity of 280 μV/mT, and an average power dissipation of 0.8 mW for 30 mA-peak sinusoidal excitation current at 100 kHz frequency.