An integrated silicon magnetic field sensor using the magnetodiode principle

We report a novel integrated magnetic field sensitive device. Its structure is reminiscent of the bipolar transistor, but its operation is essentially that of a magnetodiode: a reverse-biased p-n (collector) junction plays a role similar to that of the high recombining surface of classical magnetodiodes. The device can be manufactured in standard bulk CMOS or bipolar technology. Sensitivity up to 25 V/T at 10-mA current is achieved. Voltage-current characteristics shows saturation and negative resistance regions, which are explained by JFET and UJT effects, respectively.