n Zener breakdown the depletion region of pn junction diode is____________________a)none of the mentionedb)Narrowc)collapesd)wider

In Zener breakdown, the depletion region of a pn junction diode is wider (d).

Here's why:

The Zener breakdown occurs in a heavily doped pn junction diode, where the depletion region is very thin. When the reverse bias voltage is increased, the electric field across this thin depletion region also increases. At a certain high electric field, the loosely bound valence electrons gain enough energy to break free and jump into the conduction band, thereby increasing the number of charge carriers. This sudden increase in charge carriers causes a sharp increase in current, leading to the breakdown of the diode. This phenomenon is known as the Zener breakdown.

So, even though the depletion region is initially thin in a heavily doped diode, it becomes wider during the Zener breakdown due to the increase in charge carriers.