High Field Resolution Hall Sensor Based on AlSb/InAs 2DEG for Magnetic Particle Detection

There is growing interest and need for magnetic field sensors that simultaneously possess broad dynamic field range and high field resolution. Semiconductor-based Hall sensors are attractive candidates for such applications, and however, the field resolution needs to be further improved. In this work, we demonstrate that the Hall sensors based on AlSb/InAs 2-D electron gas (2DEG) exhibit high magnetic field resolution over a broad field range at room temperature. The sensor achieves a minimal detectable magnetic field of0.25 \; μT/Hz0.5@3 kHz and a sensitivity of 570 V/(A·T). Moreover, the sensor maintains better than 99% linearity across a magnetic field range of ±4 T, with a temperature coefficient of 0.22% K^-1. By applying a gate voltage to suppress the 1/f noise, the magnetic field resolution is further improved to0.027 \; μT/Hz0.5@3 kHz. Using such Hall sensors in the differential magnetometer configuration, we successfully measure the hysteresis of the perpendicularly magnetized MnGa microparticle. These findings pave the way for the development of high resolution and ultrawide dynamic range AlSb/InAs 2DEG-based Hall sensors.