Question

Answer in brief.

How is a Zener diode different than an ordinary diode?

Answer 1

A Zener diode is heavily doped, with doping concentrations greater than 10¹⁸ cm^-3 in both the p- and n-regions, whereas an ordinary diode has doping concentrations of 10¹⁷ cm^-3 or less. As a result, the peak inverse voltage (PIV) of an ordinary diode is greater than that of a Zener diode, and the breakdown occurs through impact ionisation (avalanche process). Other than that, their I-V characteristics are similar.