A Zener Diode works on the principle of
A. Tunneling of charge carrier across the junction
B. Doping of charge carrier across the junction
C. Diffusion of charge carrier across the junction
D. None of the above

Hint: A Zener diode is a silicon semiconductor tool that allows present-day to waft in either a forward or opposite direction. The Zener diode has a nicely-defined reverse-breakdown voltage, at which it starts accomplishing contemporary, and keeps operating continuously within the reverse-bias mode without getting broken.

Complete step by step answer:
Zener diode works beneath the breakdown region of the p-n junction. It operates in the breakdown place of a p-n diode whilst a high opposite voltage is carried out throughout the diode and opposite voltage exceeding the breakdown voltage. This outcome within the tunneling of electrons from the valence to conduction band studying to a huge number of loose minority carriers that unexpectedly boom the opposite modern.
Zener diodes are used for voltage law, as reference elements, surge suppressors, and in switching applications and clipper circuits. The load voltage equals the breakdown voltage VZ of the diode. The series resistor limits the contemporary through the diode and drops the excess voltage whilst the diode is carrying out.

Hence option A is the correct answer.

Note: Zener diodes are heavily doped than normal diodes. They have got an extra thin depletion location. While we follow a voltage extra than the Zener breakdown voltage (can range from 1.2 volts to two hundred volts), the depletion region vanishes, and a massive present day starts off evolved to go with the flow via the junction.