Question

In the depletion layer of the p-n junction diode, there are presents.
A. Only holes
B. Only electrons
C. Electrons and holes both
D. Neither electron nor hole

Answer 1

p-n junction diode is two terminal semiconductor devices which allow the flow of electric current only in one direction and it blocks the flow of electric current from the other direction. The p-n junction is formed when the p-type and n-type semiconductor are joined together.

Complete step by step answer: We know that when a p-type and a n-type semiconductor are joined together then the electrons in the n-type move across the to p-type region whereas the holes in the p-type move across the n-type region and this creates a layer known as the depletion layer.
In this region both the electrons and the holes are present, hence we can say in the depletion layer of the p-n junction diode both the electrons and holes are present.

Option C is correct.

Note: Width of the depletion layer in a p-n junction diode increases as charge carriers are swept into battery terminals, holes from p-type into negative terminal and electrons from n-type into positive terminal.