High sensitivity CMOS microfluxgate sensor

摘要

The first microfluxgate based on a standard CMOS process is presented. The ferromagnetic sensor cores are electrodeposited at room temperature on top of the chip passivation. The post-processing is fully compatible with all standard IC technologies. The second harmonic of the sensor output voltage exhibits a linear response to small magnetic fields below 50 /spl mu/T. The linearity error including hysteresis is smaller than 1.2% full scale. The angular field response deviates less than 1.6% from a sine function. The sensor has a maximum sensitivity of 2.7 V/T at 2 MHz at a power consumption of 60 mW. The equivalent signal noise is 6 nT//spl radic/Hz at 10 Hz.