Low-cost 2DEG magnetic sensor with metrological performances for magnetic field and current sensing

We have developed Hall sensors featuring a two-dimensional electron gas (2DEG) in a AlGaAs/InGaAs/GaAs delta-doped heterostructure. They show a large sensitivity (750 V/A/T), a low thermal drift (-140 ppm//spl deg/C), an excellent linearity vs. magnetic field. Their gain and offset have a very stable behavior under temperature cycling, making them well-suited for current sensing. They are practically free from backgating induced pinch-off effects, which makes them suitable for power measurement. All these characteristics are reproducible within a few percents from run to run.