What is p-n junction?

A p-n junction is a semiconductor interface formed by joining p-type and n-type materials. The p-type side contains an abundance of holes (positive charge carriers), while the n-type side has excess electrons (negative charge carriers). When these two types are brought together, electrons from the n-side recombine with holes from the p-side, creating a depletion region that establishes an electric field. This characteristic enables the p-n junction to function as a diode, allowing current to flow in one direction while blocking it in the opposite direction.