Fluxgate-Type Magnetic Microsensors for Wide Linear Measuring Range

In this paper, we present a microfabricated fluxgate sensor for wide linear measuring range applications. The sensor consists of an electroplated copper excitation rod surrounded by an electroplated Permalloy core layer, and has planar pick-up coils for signal detection. Fabricated sensors are tested in orthogonal and parallel operation modes. The effects of operation modes and excitation conditions are compared. A linear operating range of ±900 μT is proved in the orthogonal mode, whereas the same sensor has much lower linear range in the parallel mode. The use of the sensor in a contactless current measurement application is also presented.