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Question
A zener diode is fabricated by heavily doping both p- and n- sides of the junction. Explain, why?
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Solution
It is a heavily doped p-n junction. As a result, the depletion region formed is very thin and the electric field of the junction is extremely high even for a small reverse bias voltage.
The I-V characteristics of a Zener diode are shown in the figure below:
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