In reverse bias, the positive terminal is connected to the n-side and negative to the p-side.

• This supports the built-in barrier, widening the depletion layer and preventing majority carriers from crossing.
• However, a very small current called the reverse saturation current ($I_0$) flows due to the drift of minority carriers (which are pushed across the junction by the field).
• This current is nearly independent of the reverse voltage (until the breakdown voltage is reached).