for an ideal p–n diode is: where Increase in reverse bias does not allow the majority charge carriers to diffuse across the junction.
However, this potential helps some minority charge carriers in crossing the junction.
Since the minority charge carriers in the n-region and p-region are produced by thermally generated electron-hole pairs, these minority charge carriers are extremely temperature dependent and independent of the applied bias voltage.
The applied bias voltage acts as a forward bias voltage for these minority charge carriers and a current of small magnitude flows in the external circuit in the direction opposite to that of the conventional current due to the moment of majority charge carriers.
A common rule of thumb is that it doubles for every 10 °C rise in temperature.