An Analytical Theory of Piezoresistive Effects in Hall Plates with Large Contacts

Figure 3

(a, b) Angle between electric field and current density in a device of Figure 2(b) operated like in Figure 2(b). The plots were obtained by FEM simulations with COMSOL MULTIPHYSICS. In (a) we have zero magnetic field and small mechanical stress . In (b) we have zero stress and even large magnetic field with 51.078° Hall angle. As predicted by [28] the Hall angle is perfectly homogeneous throughout the device (b), whereas in the piezoresistive case (a) the angle varies between −0.446° at the supply contacts and in the major portion of the device and +0.446° at the sense contacts. Therefore the analogy [2] between Hall effect and piezoresistive effect does not apply in this case.

(a)

(b)