Answer to Question #113076 in Atomic and Nuclear Physics for Amina

Question

What is the cause of reverse saturation current?

Answer 1

In a PN junction diode, the reverse saturation current is due to the diffusive flow of minority electrons from the p-side to the n-side and the minority holes from the n-side to the p-side. In a reverse characteristic of pn junction,current increase with respect to reverse voltage. When voltage breakdown occurs, current remains constant and not increase even though there is increase of voltage. This current is known as reverse saturation current.

Hence, the reverse saturation current depends on the diffusion coefficient of electrons and holes. The minority carriers are thermally generated so the reverse saturation current is almost unaffected by the reverse bias but is highly sensitive to temperature changes.