Question

why hall effect is much greater in semiconductors than in metals?​

Answer 1

Explanation:

Hall voltage is inversely proportional to the carrier concentration. Metals have carrier concentration in the 1E23/cm^3 range, about one electron per atom. The maximum carrier concentration in a semiconductor is 1E19/cm^3… 1000 times smaller than the metal. That would imply that the Hall voltage would be about 1000 times larger, volts instead of mV for reasonable current and magnetic field.