Hall sensor:

The Hall effect is a kind of magnetoelectric effect, which was discovered by A.H.Hall (1855-1938) in 1879 while studying the conductive arrangement of metals. Later, it was found that semiconductors, conductive fluids, etc., also have this effect, and the Hall effect of semiconductors is much stronger than that of metals, and various Hall components and information processing made of this phenomenon are used. Hall effect is a fundamental method to study the function of semiconductor materials. Hall coefficient and other important parameters are determined by Hall effect experiment.