PN Junction

A PN junction is a boundary where two types of silicon material—P-type (positive) and N-type (negative)—are joined together. P-type silicon has extra "holes" or missing electrons, acting like positive charges, while N-type silicon has extra electrons, acting as negative charges. When connected, these materials create an electrical barrier that allows current to flow in one direction when a voltage is applied, enabling the functioning of diodes and transistors. This junction is fundamental in electronic devices, controlling the flow of electricity to power circuits efficiently and reliably.