PN Junction: Current flow in Reverse Bias

[Prannoy Mehta]

Can someone explain why after a certain voltage, current flows. We were taught that in pn junction when a reverse voltage is applied the depletion region grows wider. Using this no matter what the voltage current should not increase. So why does a current flow when a reverse current is applied.

 

[Drakkith]

I believe it's due to avalanche and Zener breakdown in the diode. Try these articles if you haven't already.

https://en.wikipedia.org/wiki/Avalanche_breakdown
https://en.wikipedia.org/wiki/Zener_effect

 

[Prannoy Mehta]

No I have not. I well read it now. Thank you.