2018/12/02 by Karen M. Dowling, Dowling, Karen M., Hannah S. Alpert +13
Engineering · Materials Science · #Applied Physics (physics.app-ph) #Composite material #Computer science #Condensed matter physics #Current (fluid) #Electrical engineering #Electrical resistivity and conductivity #Engineering #FOS: Physical sciences #Hall effect #Magnetic Field Sensors Techniques #Materials science #Offset (computer science) #Optoelectronics #Physics #Plasma Diagnostics and Applications #Spinning #ZnO doping and properties
paper · pdf · doi:10.48550/arxiv.1812.00363
openalex publication_date 2018/12/02 · openalex created_date 2018/12/11 · openalex updated_date 2026/07/28
This letter describes the characterization of a low-offset Hall-effect plate using the AlGaN/GaN two-dimensional electron gas(2DEG). Four-phase current spinning was used to reduce sensor offset voltage to values in the range of 20 nV, which corresponds to a low residual offset of 2.6 micro-Tesla when supplied with low voltages (0.04 to 0.5V). These offsets are 50x smaller than the values previously reported for GaN Hall-effect plates, and it is on par with state-of-the-art silicon Hall-effect plates. In addition, the offset does not exceed 10 micro-Tesla even at higher supply voltage of 2.34V. The sensor also shows stable current-scaled sensitivity over a wide temperature range of -100C to 200C, with temperature drift of -125 ppm/C. This value is 3x better than state-of-the-art Silicon Hall-effect plates. Additionally, the sensor's voltage sensitivity (57 mV/V/T) is also similar. Because of their low offset values, AlGaN/GaN Hall-effect plates are viable candidates for low-field and high temperature magnetic sensing in monolithic GaN systems used in extreme temperature environments such as power inverter, down-well, combustion, and space applications.