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 (BY and BZ) by relying on the difference between base and collector currents (ΔICB). 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 BY and BZ 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.