Assertion: In a semiconductor diode, the reverse biased current is due to drift of free electrons an

Question

Assertion: In a semiconductor diode, the reverse biased current is due to drift of free electrons and holes. \ Reason : The drift of electrons and holes is due to thermal excitations.

Professor PC Thomas Classes · Answer

(b) : A reverse bias on a $p-n$ junction opposes the movement of the majority charge carriers thus stopping the diffusion current. It makes the free electrons and holes to drift across the junction. Therefore a small current in $\mu \mathrm{A}$ flows even when the $p-n$ junction is reverse biased. Drift of electrons and holes is associated with electric field and thermal excitations.