- Semiconductor diode

It is a diode made up of semiconductor components. The cathode, which is negatively charged and has an excess of electrons, is placed adjacent to the anode, which has a positive charge, carrying an excess of holes. Here, a depletion area forms, with neither holes nor electrons. A positive voltage at the anode makes the depletion region small, and current flows; a negative voltage at the anode makes the depletion region large, preventing current flow.