ABSTRACT
In the language of semiconductor physicists, the mobility of the electrons is higher in semiconducting material than in metal. Silicon has a high Hall constant, but there are other semiconductors that show higher electron mobility and therefore higher Hall constant. When the current is transported by negatively charged electrons, they will move from right to left. The product of velocity and charge is the same, and the charges always accumulate in front. This means that, if the current is transported by electrons, the front electrode will become negative. If the charge is transported by holes in a semiconductor, then the front electrode will become positive. Classic fluxgate sensors are made by winding copper wires. Of course, MEMS people tried to develop a planar fluxgate using thin film coils, and this actually works.
