Question

what happens at zener breakdown?

Answer 1

Dear student,
​​​​​​ The basic principle of zener diode is the zener break down. When a diode is heavily doped, it's depletion region will be narrow. When a high reverse voltage is applied across the junction, there will be very strong electric field at the junction. And the electron hole pair generation takes place . Thus heavy current flows. This is known as zener breakdown.
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