Study of SOI Field-Effect Hall Sensors in the Partial Depletion Mode

Earlier, when studying with the help of instrument-technological simulation of the silicon-on-insulator field-effect Hall sensor (SOI FEHS) in the partial depletion mode, the effect of increasing its magnetic sensitivity was discovered. In this paper, we study the parameters of SOI-FEHS samples in various operation modes to experimentally confirm the discovered effect. To increase the measurement accuracy in the partial depletion mode, the FEHS design with a split drain is used. The optimal values ​​of the load resistances of the bridge circuit are determined. An analysis of the results of studying the experimental SOI-FEHS samples shows that the peak of the increased magnetic sensitivity is observed in the partial depletion mode. At a load resistance of 1 MΩ and a supply voltage of –9 V, the maximal magnetically induced signal approximately triples in the partial depletion mode compared with the full depletion mode. When recalculating the ΔU voltage difference on the load resistances to the magnetic sensitivity, the specific magnetic sensitivity of the FEHS in the partial depletion mode can reach values ​​of about 105 V/(A T), which is significantly higher than that of semiconductor Hall elements.