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

Figure 4

(a, b) Angle between electric field and current density in a device of Figure 2(a) operated like in Figure 2(a). 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), but surprisingly in the piezoresistive case (a) the angle is also highly homogeneous (it varies only between −0.445766° and −0.445752°). This seems to be the reason why the analogy [2] between Hall effect and piezoresistive effect works for this device.

(a)

(b)