Modeling and Performance Optimization on GaN Sectorial Split-Cathode Magnetic Sensors

The modeling and sensitivity enhancement work was carried out on the AlGaN/GaN-based sectorial split-cathode magnetic sensors. An analytical model is proposed to offer a guide for performance optimization. Devices with different geometric designs were fabricated and characterized for the magnetic response by the Hall effect-induced current difference for model verification. The results show that the magnetic sensitivity is linear to the carrier Hall mobility and dependent on the channel and electrode geometries. Furthermore, the model highlights that the sensor design with a 60° sector angle and a channel length approximately ten times in ratio larger than the anode radius will obtain the maximum sensitivity. The optimal device fabricated gives a magnetic sensitivity as high as 62.05% T−1 and with the minimum detectable magnetic field of 55 \mu \text{T} in measurement.