Performance and applications of a two axes fluxgate magnetic field sensor fabricated by a CMOS process

Fluxgate magnetic field sensors offer a wide field of applications in the nT and T range. The thin film fabrication of the solenoids in the metalization layers and the core in the intermetal dielectrics of a CMOS process has been successfully developed in recent years. Using these monolithic integrated two axes fluxgate magnetic field sensors a system has been built, that enables sensitivities from 5 to 30 mV/T, optimized for the detection of the earth's magnetic field. The operating temperature range from -40 to 125°C and low temperature drifts of typically 100 ppm/K arise applications like electronic compasses, detection of the earth's magnetic field and its variations (e. g. caused by vehicle traffic) and non-destructive testing in a low-cost market segment.