Question

Explain the formation of potential barrier in a p-n junction.

Answer 1

$\Rightarrow$ It is a junction formed by joining

p-type and n-type semiconductors together in very close proximity.

$\Rightarrow$ At the instant of $PN$-junction formation free electron near the junction diffuse across the junction into the $P$ region and combine with holes whereas, filling a hole makes a $-ve$ ion and leaves behind a $+ve$ ion the $N-$ side.

These two layers of $+ve$ and $-ve$ charges from the depletion region depletes the flow of free charge carriers.

$\therefore$ Potential Barrier is formed.