New high resistance magnetic sensors based on nanogranular Ag-Co ferromagnetic alloys

One of the most important problems in the development of thin film metallic sensors is to obtain a high resistance value. This paper presents the design, fabrication and test of new structures of contactless magnetic sensors based on high-sensitivity giant magnetoresistance. In order to obtain high resistive values, the samples have been patterned as meanders with circular and semicircular configurations. The physical principle of these sensors is the magnetoresistance measured in an Ag-Co alloy, which has been optimized to obtain a high sensitivity. The tests have been carried out using a measurement bench for circular shapes fabricated ad-hoc for the designed devices.