Question

How does a P-N Junction in reverse bias allow current to flow through it? Is Zener Diode the same as a P-N Juction in reverse bias?

Answer 1

in a reverse biased PN junction, there is no current flow from majority charge carriers through the device, because there are no majority charge carriers within the depletion layer. However, a small leakage current will flow, due to minority charge carriers from electron hole pair generation. (The depletion layer effectively forms a very high resistance layer between the conductive regions, which only allows a small leakage current to flow.)

2-yes, both are same after a specific voltage applied