The magnetotransistor for 2-axis magnetic field measurement in CMOS technology

This paper presents a magnetotransistor for detecting magnetic field in vertical and lateral directions (B
Y
and B
Z
) by relying on the difference between base and collector currents (ΔI
CB
). It was designed and fabricated using CMOS fabrication technology. The device structure consisted of one emitter, 4 collectors and 4 bases. The experiment showed that, at 10 mA of biasing current, the B
Y
and B
Z
direction sensitivity to magnetic field within the range of 0 – 400 mT are 0.7 and 1.35 %/T, respectively. The sensitivity at emitter current 20mA are 0.55 and 0.7 %/T for vertical and lateral magnetic field directions, respectively. This research on the magnetotransistor produced magnetic sensors with small size, high performance with wide range of applications.