Question

A Zener diode

• A. is a heavily doped in reverse bias junction diode.
• B. is a lightly doped in forward bias junction diode.
• C. is a lightly doped in reverse bias junction diode.
• D. is a heavily doped in forward bias junction diode.

Answer 1

The correct option is A is a heavily doped in reverse bias junction diode.

The Zener diode works on reverse bias. The reverse breakdown voltage depends on doping of the diode.

Hence, in the Zener diode, the heavy doping of its $p-n$ junction is done.

The depletion region formed in the diode is very thin $(<1\mu \text{m})$ and the reverse bias voltage of about $5\text{V}$ which is less than ordinary diode.

Hence, $\left(\text{B}\right)$ is the correct answer.