Drift current Is of PN junction under open-circuit conditions

anhnha · Jun 13, 2013

Hi,
I need help to understand this section from my book.

Diagram of a PN junction showing holes on the left p side, free electrons on the right n side, bound charges and the depletion region in the middle, with drift current I_D and saturation current I_S arrows pointing in opposite directions.

Printed textbook paragraph on the drift current Is and equilibrium of a pn junction, with the sentence stating Is is strongly dependent on temperature but independent of depletion-layer voltage V0 underlined in red.

Here we are considering drift current Is of PN junction under open-circuit conditions.
I don't understand why the drift current Is is indepentent of the value of the depletion layer voltage Vo.
I think the voltage create an electric field that helps minority charges in N, P materials establishing drift current Is. Therefore, it is of course dependent on Vo.
Can you tell me where I am wrong here?

mfb · Jun 14, 2013

I think it is assumed that all generated minority carriers reach the junction. The generation process does not depend on the voltage.

Drift current Is of PN junction under open-circuit conditions

Discussion

Similar threads